Hello,
That would be a shed phase going on.
I am sorry the vet manhandled him so badly. I hope he didn't injure him though, do you think she did?
I don't think he needs the medication though, if no infections were found, etc. A fecal was not done either?
He may be brumating somewhat if he is not eating a lot. Or shedding can also slow down their appetites, too.
Is he maintaining his weight or losing weight?
Blood work would be a good idea as well just to get an idea where his baseline levels are.
Let us know how he is doing. I hope his aggression gets better.
Tracie