I rewatched and I've been thinking this over. There's something absolute about Ahsoka banished/left for dead without revealing Barriss' interference to the rest of the Jedi. Ahsoka may even never figure out whodunnit. Maybe Maul is manipulating Barriss? I can't figure out the motivation but Barriss' character may end not being revealed as the traitor (or the manipulator). But whoever attacked Ahsoka has serious skills.
The finale trailer: