I think he actually went by FBI synopses of the tapes, not just a catalogue of them. And if his widow wanted the tapes sealed that could only serve to verify what is allegedly on them. In reading 6 or 8 histories of the FBI over the years these tapes were always addressed, and various authors arrived at similar conclusions regarding the veracity of this particular report. I don’t know about the rape incident but I don’t think there is any doubt that he was a very active philanderer. His contemporaries in the civil rights movement have all acknowledged it.
You are correct.
I think the only real thing up for dispute is the allegation about the rape incident.
Given everything else..it’s plausible.
I suspect the pervert part of this is orgies and doing it back end style which back then would be considered an unnatural act. Or perhaps the orgies were also men doing it with each other.
None of this should be a problem for libs except the rape part.
The Sixties were... swingin’...