Croqueteer,
welcome to the thread.
Your questions have been asked several times before. May I respectfully suggest you read the thread from start to finish and visit the campaign website. That should provide you with some answers.
However, I would ask that you bear in mind the rules in place at the time that in order to find deceased aircraft negligent, there had to be absolutely no doubt whatsoever.
Kind regards,
Brian
"Justice has no expiry date" - John Cook