Do us all a favor and sue the head guy for breach of contract. At a minimum, he should have to make restitution to the team parents for whatever amounts he netted to himself, due to his failure to keep his end of the bargain.
I don't care if he picked the team or not. If you make specific promises, and the people to whom you make those promises pay you the exact amount of money you requested in exchange for those promises, then you have to keep your promises or else face the consequences. If one of your employees quits, you have to take steps to assure that the team experience remains what you promised.
It's not just baseball, it's a services contract, and the law applies here just as it does anywhere else in the universe. There is no baseball exception to contract law.
Too bad you're not here in VA, it'd be fun to represent you pro bono. Nothing like getting served with 12 separate small claims court cases to get your attention!