PA and AS should each be dealt with on their own individual terms. One shouldn't depend on the other.
And although PA hasn't been accused of actual rape or actual paedophilia, surely even he with his limited intellect had some grasp that his presence would lend an air of respectability and prestige to a party where underage girls were being exploited.
Again, perpetrators of sexual exploitation depend on witnesses and victims remaining silent. Or, as with many victims of the Rotherham case, they demanded silence through intimidation. PA allowed himself to be used as a "respectability blanket" in return for financial assistance, flattery, or other more dubious perks. For those reasons, he should do everything he can to assist the FBI.
And remember that in 2010 PA willingly returned to stay for four days in the NY home of JE who had pleaded guilty to sexually abusing a 14 yr old in 2008 in a case brought by the girl's parents, which according to the following quote from Wikipedia was just the tip of a very large iceberg:
Quote from Wikipedia
"In 2005, police in Palm Beach, Florida, began investigating Epstein after a parent complained that he had sexually abused her 14-year-old daughter.[6] Epstein pleaded guilty and was convicted in 2008 by a Florida state court of procuring an underage girl for prostitution and of soliciting a prostitute.[7] He served almost 13 months in custody, but with extensive work release. He was convicted of only these two crimes as part of a plea deal; federal officials had in fact identified 36 girls, some as young as 14 years old, whom Epstein had sexually abused.[8][9]"