K.M.
I'm so suprised and disappointed in your doctor. I'm also suprised that the dentist didn't have more to say about it, and that they put the braces on her while she was still sucking her thumb. I don't blame you for not wanting to waste your money. You said you have tried the yucky tasting stuff, but did you try hot tasting stuff, like tabasco, or even real yucky stuff like vinegar? The other thing I thought of was how about a splint on her thumb? There is always the other way of thinking of it too, rewards for every day she does not and once she reaches a set goal she gets a reward. Good luck!
K. M