The answer is to file a federal civil rights lawsuit against the officer and the university. First of all, it removes the matter from state court where the university would be comparatively untouchable, second, while economic damages to the preacher would be minimal, the defendant would be liable for his attorney fees.
Well that should also happen, but the fact remains, “Threatening Criminal Action” where no crime has been committed is still FELONY EXTORTION in every state, Regardless of who does it.