Oh my...I am so sorry for what happened to your poor Dolly!
I could pretty much "ditto" what everyone else has already said. Please, do take pictures, and consider pursuing this further. I hope your friend, Dolly's vet, can help you, without getting caught in the middle. I'm glad you have the one vet you like so much, but it's too bad she can't move to another practice. I imagine there might be times you would have to make an appointment for Dolly and she won't be there that day, or won't have an opening. Then you might be "stuck" with the vet who, I feel, acted very unprofessionally and unethically today.
We won't even get into how the groomer acted!!!
I know you said you are going to find another groomer. Good! I have to say that when I brought Lexi for her first grooming, I stayed with her, and I was NOT happy with the experience. I found another groomer, who was recommended, and oh my - what a difference! Not only was Lexi nicely groomed, but her behavior overall was improved at home. And now I brush her every single day, without all the biting I had gotten from her in the past. I'm telling you, she would bite the heck out of the brush, or my hand - whatever she could reach - before that.
My point is that not only can a negative experience have negative results, but a positive experience can actually bring positive changes as well. I think you and Dolly both with be much happier with a new groomer.
Good luck, and please keep us posted!