As Pete said, they have to prove actual damages in order to get a judgment for any amount of money.
My guess is that they know this. The goal is to drain O'Donnell's bank account (via the costs of litigation, not necessarily a judgment), intimidate other exJWs, and track down the JWs who spoke to him. They are demanding a list of "every Jehovah’s Witness [he has] communicated with in the last five years regarding the faith of the Jehovah’s Witnesses." They want to clear out anyone who is providing information to critics. They know they have quite a lot of PIMOs who leak information, and they want to find as many of them as they can.