Here is one hypothetical explanation for this behavior: maybe Craig is not Satoshi, but he wants to know who the real Satoshi is. So he fabricates some evidence, and goes public claiming to be Satoshi, hoping that the real Satoshi will contact him. Once that contact is made, if he figures out Satoshi's true identity he can then blackmail that person, or if not he can extort money from them in exchange for dropping his claim. Probably farfetched..