I really don't have anything to add to what everyone has said as they have covered it all!
I DO think you should go to a vet dermatologist. Poor baby needs some relief and it sounds like that has not happened with either of your vets.
I have allergy pups and know how frustrating it is, but seriously they should not look as bad as the pictures you have provided. She must be miserable.
Good luck to you! ... and welcome to YT
