Racketeering? That word doesn't mean "really really bad, nefarious stuff." Racketeering is a financial crime, including extortion, loansharking, bribery, and obstruction of justice in the furtherance of illegal trade. Bernard Law may have been extorted, bribed, etc., for all we know, but have you ever heard of him extorting or bribing someone? (Out-of-court settlements are not legally bribes, even if they seem to be morally equivalent.)
Aiding and abetting? Abetting involves material assistance and encouragement of known criminal behavior. If some guy runs into your home carrying sequentially ordered dollar bills, and asks you where the nearest bank is, you may suspect he is a criminal. One might figure you'd have to be an idiot NOT to suspect he was a bank robber, but if you give him directions to a bank, you are NOT guilty of aiding and abetting. On the other hand, if the police inform you that Joe Schmoe is wanted for a bank robbery, and you purchase airline tickets for him, that's aiding and abetting.
Now, suppose a priest actually even CONFESSED to sexually assaulting a child. The confessor doesn't have to hand the priest over to the police, and if he did, there'd be no admissable evidence for the police to do anything about it. The confessor is granted the same immunity as a lawyer or a psychiatrist, and for the same reason.
Unless the confessor has a moral certainty that the priest will commit the crime again, he CANNOT report what has been confessed to him. Furthermore, a part of the act of confession is a statement of a sincere commitment to NOT commit the act again.
But, in truth, the issue of confession is a red herring, mostly created by anti-Catholic Hollywood types. The truth is that most of these sickos didn't believe they did anything wrong and wouldn't confess. Even if the confessor SAID he was absolved, if the penitent priest didn't sincerely resolve to never commit the act again, no absolution occurs. Maybe some "Godfather: types may not know that, but you bet your keister priests do!"