moving right along...
David, Plucky's suggestion about reporting your T to the licensing board, or whatever it is, is an excellent one.
You might combine that with a request for a refund, if you're serious about seeking one. I believe that these boards do sometimes handle things like that, or at least can refer them to mediation... depending on where you are.
If you try that, you'll probably be most likely to succeed if you write the stuff you REALLY want to say, all hot and strong, and then put that in a desk drawer [or the freezer!] and write a very detached description of events... then wait a couple days, read the 'cool' version again, and if it covers everything, send THAT one to the board. We humans tend to attack strangers who express strong feelings, rather than supporting them, all too often. Don't know why. But it happens all the time.
Incidentally, enclosing a notarized (!) copy of whatever letter this T sends you, with your letter to the board, would probably clinch it, if you write your letter calmly and comprehensively.
Speaking of 'hot and strong', the best way to know if you have a winnable malpractice case is to find out if lawyers would take it on contingency. For future reference. This, I actually do know about. But I am not suggesting you bring a suit. This is just info in case you find you are really hungry for justice and that option becomes almost irresistible in your mind. Remember, then: (a) the law isn't about justice, unfortunately; and (b) if a reputable lawyer won't take the case on contingency, you don't have a case... they won't tell you that in so many words, but the actions say it all.
Good luck David. Thank God you found this board before your T did this hideous thing.