First, the was a LEO (either a sheriff or prosecutor) who emphasized that he was a Democrat and he didn't want to be involved in a witch hunt on Ted. So he admitted that inconsistencies in the stories and events weren't pursued. He never expressed any desire to get to the truth. He seemed to imply that he know what it was and he didn't want to go there.
Second, one of the Boiler Room Girls maintained that there was no sex involved. Sure. Six older men (many of whom were married) and six younger girls for a party. That's the kind of naivete or secret-keeping that hounds love to hear. They admit there was lots of alcohol there but no sex? Sure. Come on, the secret's been out for years - we all know what kind of sleaze balls the Kennedy clan and its associates are. I would guess that there was never a vulnerable young female around Joseph, Sr., Joseph, Jr., John, Robert, or Ted who wasn't at risk (and let's not forget Rose looking the other way). The Kennedy's are scum at the Clinton level.
BTW, one of the cool things about the movie was all the extinct car brands that appeared: Oldsmobile (of course), Pontiac, Rambler, Plymouth, International truck. I didn't see a Studebaker but it wouldn't surprised me to learn that I just missed one.
Yes, that's the elephant in the room never mentioned. Six older - well, slightly older - married men off to a beach party with younger, single women with the booze flowing freely and it's all just innocent fun?! Right! And these women, the Boiler Room Girls, have been steadfastly silent for fifty years suggesting to me they were handsomely rewarded for same (one, Esther Newberg, was very high up in a publishing house and is now a bigwig at ICM, so maybe her buy-off was professional advancement).