There are a few problems with this:
- The opt-in structure doesn't solve the antitrust problem at all. Revenue sharing is capped, which is a pretty straightforward section 1 violation, and anyone who opts in is just opting into an illegal agreement.
- People can't become part of a class in the future. The class is defined now (it has to be because class members have a right to object to the settlement). Anyone who isn't yet a class member wouldn't have a right to object before final approval, so it wouldn't be fair to bind them. That would be inconsistent with Rule 23, and probably a violation of Due Process as well.
- If the settlement persists, then any non class member who later attends a revenue sharing school will have a claim.
- The fact that the district court thinks this is okay doesn't mean it is. The objecting class members have a right to appeal immediately. And anyone who isn't part of the class can just go ahead and file a new lawsuit in the future. District court rulings have no precedential value (they're only binding in the future as to the parties who were actually before the court), so other districts courts, not to mention appellate courts, wouldn't have to follow it.
- Even aside from the likely illegality of trying to bind non-parties to a settlement, the terms should probably be void for the simple reason that you can't settle a lawsuit on terms that will require one of the settling parties to commit an ongoing felony for an indefinite period in the future.