Teddy Riley signed the contract to produce material and promote the album BEFORE he heard the songs. After he heard the songs he said to Taryll that the vocals are not MJ. But he was already under contract. He could have leave the project and face legal actions (which he should have done) or stay and work on them. Taryll wasn't under any kind of contract so he could leave and talk whatever he wanted. Teddy's contract probably had expiration date because in recent DJ Vlad interview, he admitted that the vocals are not MJ.