So in summary:
1. In due course, the UK AAIB will produce their report summarising their considered view on what is likely to have happened. Along with many reading and contributing to this forum, I now have my own view - based on the original circumstances and the many, many valid inputs provided in this forum.
2. The US FAA have little practical interest, as they are not responsible for enforcement outside the US, the pilot involved is no longer with us and so has no US licence to lose, and the practical owners (whoever and wherever they may turn out to be) do not operate in the US.
3. The UK CAA will continue to give this murky area the good ignoring which appears to have gone on for years. A moderate increase in carefully judged enforcement action would probably do something at little cost to level the playing fields between those who play by the rules - and incur the costs thereof - and those who cheat the system and thumb their noses at the formal checks and balances. That those checks and balances are based on painful experience seems never to register with those cowboys. There doesn't seem to be any shortage of relevant regulation - just an appalling lack of responsibility in monitoring and enforcing.
4. The extent to which the responsibilities of those behind this whole sorry saga are exposed will be based on the various financial and 'political' interests of the parties. With some £15M in play and some deep pockets to keep the lawyers busy, this one could run and run.

Cynical? Moi?

Yep, this all comes down to insurance. It is fair to assume that Mr Sala, in particular his footballing prowess, was insured by someone and that policy will be cashed-in. For sure the prime underwriter will be looking to minimise his exposure and he will spend a lot of money in pursuing other parties in order that they pay for their part in the loss. The cause of the crash is (probably) largely irrelevant.

I can 100% assure the nay sayers that the UK CAA Enforcement branch are taking this very seriously and are pursing it VERY actively............

A new search for the body of a missing pilot David Ibbotson could start next week according to BBC Humberside. This search will also be masterminded by David Mearns who located the crashed aircraft containing Sala's body.Mearns says the new search will be "technically very different" to the discovery of the missing aircraft and is depepdebnt on good weather, neap tides and flight permits. The finding is coming from donors who have given to the Ibbotson family . Gary Lineker has chipped in £1,000

Thank you. My earlier comment was based only on the commentaries in this thread, as I had no counterbalancing information. It's a very long time since I had any contacts in/with the CAA (last thirty-odd years experience was with military aviation.) In common with many, I will be encouraged if the CAA is both resourced and supported in appropriate enforcement action(s.)

So we have someone denying ownership of the Malibu, and admitting to pay for it. He has not mentioned anything about cost sharing.
So he is paying for one party at least.

By saying that he has contracted someone else to make the arrangements, he has passed the buck onto the PIC.
It will be very hard to nail him for anything. Henderson on the other hand will be looked at under a microscope.

As for the Eclipse flights, under cost sharing, these are illegal to do so.

European and National regulations permit cost sharing as follows:

• The flight is a cost-shared flight by private individuals.
• The direct costs of the flight must be shared between all of the occupants of the aircraft, including the pilot, up to a maximum of 6 persons.
• The cost-sharing arrangements apply to any other-than complex motor-powered EASAaircraft and this includes aircraft registered outside of the EASA area but operated by an operator established or residing in the Community.
• Cost-sharing is also permitted in non-EASA(Annex II of the Basic Regulation) aircraft registered in the UK.

This encompasses N registered aircraft.
Full website can be found here.
https://www.caa.co.uk/General-aviati...aring-flights/

The buck has been well and truly passed onto Ibbotson and Henderson.

So far I have read nowhere that those flights were performed on cost sharing basis. In one of the interviews further up the page the manager (Mr.McKay) said that he paid for them. Alone. There is nothing illegal about that. Lots and lots of corporate flying is done this way: The company owns or rents a plane and either one of it's employees with a license or a contracted pilot flies it. The important thing is that no one must be invoiced for that flight.

Who has operational control? Mckay has said quite firmly several times that his company did not have operational control. That leaves Henderson having operational control and presumably his name is on the paperwork as having provided aircraft and pilot. Of course Henderson may have an entirely different view of the transaction, we don't know.

That would be Mr. McKay. It does not matter if he phones the parties involved (the owner of the plane and the pilot who flies it) himself or delegates those calls to his secretary, Mr. Henderson or Donald Duck. If Mr. Henderson, through his connections, gets a better price for the plane it would indeed be a wise move to let him do the talking. As long as the invoice for the plane is paid by him (McKay) as well as the fee for the pilot (in case he has a commercial license). The ultimate responsinbility to perform the flight within the legal frame rests with the pilot in command. I have flown like that for a large company for years. Their lawyer and their insurance people were happy with it. Countless ramp inspectors found nothing wrong with it.

How it used to be done
 

My experience has largely UK Military and police flying, I did for a period fly corporate out of a small London airfield. The company I worked for held an AOC though we were based side by side with many other aviation enterprises and shared the airfield cafe with the whole spectrum of pilot's and visitors/clients etc.
The basis of our businesses was to offer a corporate service of providing aircraft and crew for charters, most business would come via a broker, these brokers would receive a request from a client and then phone around the companies to find the best fit and lowest cost. It often became a back and forth negotiation with our ops staff. We pilot's would be allocated the task the day before unless it was a rush job.
The client would often have no idea who or what would be flying them until they arrived at the agreed pick up point. They certainly would have no idea of the pilots qualifications or the capabilities of the pilot or the aircraft.
It often turned out that the broker had promised things to the client to seal the deal that left we pilot's spinning plates on the day, or having to explain the real world to the client in an uncomfortable conversation.
It was also the case that one pilot willing to bend the rules or give in to the client could set a dangerous precedent for those that followed.

​​​​​​In summary, I'd be looking at the broker first and foremost and work out in both directions from there.

The company you work for, even though they may have delegated authority to someone else, will say that they decided what aircraft to hire and what pilot to hire. They have also informed the insurers as to how the aircraft is being operated.
I have always taken the view that Mckay could have said that he was providing his corporate aircraft for free. However his public statements don't describe that, they describe a charter provided by Henderson.
Now he may be saying one thing in public and another to the investigators. We will have to wait and see.

Art, what you've described is the work of a proper Charter Broker who one hopes wouldn't consider using a non AOC operator for their clients.
That is a world apart from an ex bookie gotten greedy...
I'm sure the sheer amount of flights this guy has organised will spark the close interest of the CAA.

Operational Control:

There is either an ops manual stating who has operational control, or it is the PIC.

"Duty of care" will be the gotcha !

Not necessarily. In a typical "corporate flying department" where a company owns (or has access to) one or more planes and employs (or contracts) one or more pilots it is the company that has operational control. It decides on the flying dates, which plane to use for what route and which pilot to assign to each flight. Under EASA part NCC an ops manual is required for that kind of flying (which would include the Eclipse of which was written above) but not a piston Malibu. Anyway the latter was "N" registered and therefore outside EASA regulations.

I knew this would be controversial and it was deliberately so. When an aircraft is being hired out to a different company every day does the PIC replicate those functions that would normally be provided by a corporate flight department? If the PIC is the only one undertaking those functions for multiple companies, is he not operating an air carrier without an AOC?

I would say no. I could get a phone call from a company that has/rents a plane telling me their regular pilot called in sick and asking me if I would fly their plane tomorrow. That does not make me an air carrier. Their plane, their passengers, their destination. I only handle the conrtrols.

Apologies, I was unclear. In my scenario, the PIC is choosing the aircraft on behalf of the company.