So Xavier has to know ..right?

After the dust settled, Xavier has to know Jane was working with Sinatra correct? After talking with his daughter he would know she was with Jane the whole time, meaning either Sinatra was bluffing about having Presley or Jane was working with her. Based on how Sinatra acted when she thought the daughter had been killed there would have been no way she was bluffing. This would also lead him to the conclusion that Jane killed Billy. Xavier does not seem to be the type to miss out that type detail.