The whole thing sounds like they made 2 separate arrests of 2 different groups and want to tie them together to jazz up the case. One group arrested in Italy, and other in the states. The take a loose tie between one of those indicted and make it one big international case, which it isn't.
The thing is Sicilian Cosa Nostra helped the Americans to cash in by putting pressure on the victims' families who still live in Sicily.
