Couldn't agree more with your sentiments pulse, particularly your last wish. I also agree that:
There is probably no more hard evidence that the airworthiness state of the HC2 was directly responsible for this accident than there is that it was caused by pilot negligence.
Although who knows what may be discovered if someone is actually looking for a change? But this is where the BoI has a role to play. Very often an Air Accident Inquiry is starved of "hard evidence", but the essence of its task is to nonetheless determine the most likely cause or causes. I would hope that is exactly what a reopened BoI would endeavour to do. As I have said it is my belief that the Gross Unairworthiness (which can now be shown) of the aircraft had a major role in its demise, and that would be reflected in the finding of the BoI. A judge armed with such a finding would have rather more ammunition in his locker than that found from "public knowledge" and the RAF would be seen to have been not merely a passive bystander in the process.