Tandem
I think you're being a little harsh there. Nine or ten witnesses on the Mull, including two trained met observers and someone who estimates he was 100 yds from the crash site said that the Mull was in fog. I don't think its a question of anyone 'wishing' that to be accepted as factual evidence so much as seeing no reason not to accept it as factual.
As regards going below the weather limits for VFR, much though it pains me to have to mention it, the aircraft did crash into terrain which nine or ten witnesses stated was in fog.
As regards to prior to waypoint change, I don't know, which is really at the heart of the matter since the verdict was based upon just that.
As regards to standards of proof, unless you question the veracity of the witnesses, it seems to me that there was absolutely no doubt that the actual crash occurred in met conditions below those required for flight in VFR even if the aircraft was flying below 140 knots. However I have been following this thread for long enough to know that someone will suggest ( or try to ram down my throat) a flaw in that argument and if they do convincingly, I will accept that.