In the Army we referred to them as “****house Lawyers” or more politely “Latrine Attorneys”. I think there are a few that hangout on various aviation forums, handing out free legal opinions and citing Wikipedia and other legal sources for support. But I think you are likely to be in good shape - most of the witnesses (assuming there were some) 50 years ago are probably dead or incapable of testifying plus if that was 8mm film, probably no equipment left to run it on or if you are really lucky, the film will just disintegrate. Had a very large case once where we had miles of computer tapes that contained data that was of interest to the plaintiffs. Problem was, the mainframe computers that read the tapes had long since been destroyed. The plaintiffs looked all over the world for something that would allow them to recover the data. Never did find anything that would work.