I haven't checked but strongly suspect there is no airline service from Nantes to Cardiff, let alone by a major airline and certainly not first class as that doesn't generally exist on short haul European flights.

Footballers travel regularilly on small aicraft. Many private jets are not much bigger than the accident aircraft and some are flown single Pilot but not commercially in Europe.

I do however agree to an extent with the point you are trying to make.

The most direct route would have been via Amsterdam

And safest in this case, which if I remember was proposed initially to the Club but it was refused in favor of this flight.
Does anyone knows if the British Club actually paid for the footballer transfer in the end ? They initially refused, there was court case , but I missed the results or if a compromise was found in the meantime

Fifa have determined that Cardiff should pay £5.1m, the first installment to Nantes. Cardiff are not paying anything and appealing the decision. If that fails they will take legal action against ‘those responsible for the crash for damages to recover its losses’.
So presumably that means the McKay agent/s Henderson and perhaps the estate of Ibbotson.

Certainly safer than the chosen option but why safest? A direct flight on a well maintained twin-turbine business aircraft flown by a professional crew of two in compliance with rules and regulations would have been just fine, would it not.

Timings at the time are back in post #110 of this thread, all on KLM Nantes-Amsterdam-Cardiff. Actually not a huge timing difference, depart Nantes 1715.

I have made my point on this in the past but even if a fully qualified pilot had been in the left hand seat the carbon monoxide leak would have produced the same result. The one thing to learn from this accident is that cheap carbon monoxide alarms are available and should be mandatory in all light aircraft.

As mentioned in this thread previously, for work purposes I've flown as a passenger in a single pilot piston engine aircraft to the Channel Islands and back with a senior French government official on board. He might not have been worth millions but the diplomatic fallout had anything happened would have been significant.

If one is in a business situation at that level where other people are making the arrangements I think it's quite natural for the passengers to assume the operation is safe. As you can read from earlier in this thread, it took me this accident and this thread for me to realise how unsafe such an operation can become, and to realise that I was probably not insured on any of the several similar flights I took.

The AAIB have a recommendation about this from July 1972, 50 years ago: 13-1972_G-AYPN.pdf (last page).

The worldwide supply of new accidents is rapidly diminishing - we need to keep recycling the old ones!