If you watch the rebels recon for the episode, Dave and Henry gilroy, one of the producers, talk about the great lengths they went to make sure their Thrawn was faithful to the books, and in a different interview Dave said that they showed Timothy Zahn the progress on him and he gave input on the process. I think they know what he means to the fans, and are treating him with the utmost respect, which is awesomeAll I want is for Thrawn to NOT end up dead once Rebels is done with him.
Pretty certain Maul shows up next episode.