@ath
I’m sorry to hear about your inner ear problems. Is there anything special to make it more tolerable?
Your GI doctor is right to refer you to a tertiary care hospital. 6 months is a long time.
Go ahead and ask your GI doctor to refer you to Mayo Clinic. If they accept you they will do whatever testing is necessary- you don’t have to ask for it. I went there for GI problems and they were extremely thorough and well organized.
If they don’t have openings you can also try Cleveland Clinic.
Let me know what you are going to do, will you?