It does hurt when they screw up! Especially when they do it in a way that touches on previous trauma. I remember T taking sides with T1 once (at least that's what I felt like he was doing) and I felt abandoned. He did own his part in it too though (your main T seems a lot like mine) and when T1 reappeared, my T was firmly rooted in my camp this time around.
I do hope your EMDR T rediscovers their autonomy and does what is right for you regardless of supervisor meddling. I have a friend who is currently stuck in the middle of her supervisor and her organisation, and I just want to say "This is your practice, not your supervisor's!"