Oh my gosh, so sorry you're going through all of this - how scary and frustrating!
I can tell you that my dog Wylie has had ear infections a few times - so I know dogs can get them. I don't understand why your vet would say they can't get them, that doesn't make sense. I would def find a new vet!
I'm worried there is something neuro going on here that is undiagnosed. Also, did you ever do the bile acid tests? I think maybe you should.
I'm going to move this thread to the Sick forum where it will get more attention
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