Cazatou,
Here we go again. The Mull lighthouse was in fog. No doubt.
The weather approaching the Mull was legal VMC, both on forecast and actual. ( Mr Holbrook, best evidence.). Weather at crash site? Who knows?
A radar fix is agricultural, good to a couple of miles at best. How precise was the timecheck to go with it?
We know the crash position. How precise was the time of impact? I bet you are using that "certified ADR", the TANS again.
Even if you have the precise figures for the above, all you can establish is accurate groundspeed.
You tell us time and time again you are an A1 pilot. Then you must understand that VNE has nothing to do with groundspeed.
Yet again you can only be basing your latest slur on the crew by taking forecast conditions as actual facts. Nobody knows the exact temperature(s), density(s) and wind velocity(s) encountered by the crew during that transit.