Thank you all for the stories and information.
I heard back from the vet I emailed and she seems quite interested in what I've told her so far. I am going to call her next week and see where we go from here! Wish me luck!
Oops, I forgot to add:
Lise... Our new vet also seems hesitant to say anything negative about another vets practices, but we do have lab reports stating that they found "overdose of cortisol steroids". My vet said that points to the dexamethasone, since that was the only steroid he was given. At least we have that going for us!