You can rest assured that Flying Lawyer is not far away.
As a past display pilot covering a fair few years I am at a loss to understand how this situation can arise.
There is only ONE place you can call if you want to practise on your home airfield and that is ATC. These two guys did just that. They asked ATC if they could practise. ATC said yes. Game over! ATC controls the sky and ATC controls the aircraft. No need to go around in circles looking for a reason to chastise this Mr Moody - he has no case. He has no authority to tell the controllers how to control the airspace under their jurisdiction. No laws have been broken if they were given permission!
It may be that the pilots were not happy about a particular part of their sequence that day and thought they should practise it. Just what I would have done, and did, many times. They are to be commended not hounded. Especially by a man who appears to have thrown a tantrum because his 'authority' was not sought and was not needed. If he, alledgedly, stormed around trying to find someone to complain to in the manner he is supposed to have done he should not be in charge of an airshow. He has certainly belittled the good name of the PFA and maybe one or two of the excellent senior members might tell him that.
Practise is absolutely vital for a display pilot.
He has to do it somewhere and that is accepted by all in authority. Think of the furore if it were found that a pilot never bothered to practise and became a cloud of dust at some airshow! He must take practise very seriously and since one was a synchro Red he practised almost every day. Groupie would be the same - and I think I know both. If that is the case - they are consummate professionals.
Give these guys a break. They know what is best and I support them 100%.