For anyone with a few hours to spare Richard D. Hall has done many hours of investigations into this case. It shows everything about her disappearance and subsequent cover up are are 'state' influenced. There is a suggestion of paedophilia and money laundering through investigation contractors.
https://www.richplanet.net/richp_genre.php?ref=185&part=1&gen=1 is films 1 to 4 and there is a total of 8 covering every aspect.
Some will brand Richard as a conspiracy nut, but he performs detailed investigation an analysis before making his own mind up and will let you decide what you think. He's covered many topics and I find his shows fascinating. He's covered the usual stuff like NASA and 9/11 but others like the Jo Cox Assasination, Didcot Murders, Derrick Bird and so on.