"What did both sides say to each other? After all that time and expense of litigation."

As you're aware, the MOU is not public information. Your best bet is to check with an attorney who has some expertise in this specific area. That's exactly what I did (some time ago) and the answer I got was: The MOU most likely states something like: Defendant agrees never to bring suit against the plaintiff in the future and the defendant agrees not to counter sue the plaintiff - or something to that effect.