Since none of us were there when this stuff allegedly happened, we never will know for sure. That's part of what makes this sort of cheating so despicable; innocent or guilty, everyone is subject to being tainted by innuendo.
As to why the trainer may offer up names that weren't really involved, you have to remember that the Fed's had him nailed for his involvement and were offering a deal. Just as with the mobsters who get a free pass for snitching on their buddies, guys like this trainer are looking out for number one. If the Fed's made it perfectly clear they were gunning for certain individuals, who is to say that the trainer wouldn't take the hint and give them the names they want? It happens in the real world all the time and is one main reason I don't support this method of law enforcement; testimony from a known criminal shouldn't count for chit without corroborating hard evidence, in my opinion.
Jerry