so sorry that your little is going thru this. I am no help with this. When we got Hot Rod is was very itchy and flakey. His ears were so dry and flakey that big flakes of skin would just come off. At one point, our first vet suspected ringworm.
We utlimately changed vets and she recommended a medicated shampoo and conditioner. I also switched foods. So far it's been under control since all of this.
Recently however I have noticed that he does tend to chew on his front paws after eating a lot of chicken.
Good luck in finding out what is wrong with your little and I hope that you can find a solution.
You've gotten a lot of great advice.