I would not perform that procedure, yet… why, read on.
By definition a vestibular migraine is a diagnosis of exclusion in which everything else has been eliminated (ICHD 1.6.3). It cannot be cured. All medications for it are prophylactic. It is believed by some that the balance function may be disrupted in the brain for VM patients.
If the nerves in your ears are “not balanced” you should look for neuromas or lesions on the nerve. That is, you more likely have a form of vestibular neuropathy. See https://www.dizziness-and-balance.com/treatment/vn_section.html for a discussion about the Vestibular Nerve Section (VNS) procedure.
In nearly all cases gentamicin should be tried first.
You may indeed have (1) Vestibular Neuropathy caused be lesion or neuroma or (2) Intractable Meniere’s Disease. Generally these are the two situations for which a VNS might be considered, but after ruling out gentamicin.
Finally, a doctor that calls a nerve imbalance in your ears Vestibular Migraine is mixing his diagnoses, in my opinion, of course.
Let me state that I am not a Doctor and all of the above is my opinion after reading many published research papers. I do have direct access to a world class research library and I am a researcher in another field; however, I am not in any respect Saha (Barrow), Fife (Barrow), Hain (Northwestern University), and about 40 others. I do consider myself more knowledgeable on VMs than the PCPs and Neurologists I have encountered except of course those 40+ above.
Why do I say this? I want you to take what I have stated and research the information and challenge your doctors. If they don’t understand possible treatments and that VM is a diagnosis of exclusion keep looking.
My current neuro in Santa Fe, NM, US has demonstrated he has a little knowledge with meds all mixed up and dosing all over the board. He has never taken a history from me and refuses to listen or consider any other information - He thinks he is a super star with VM and that makes him dangerous. As a result we are flying back to Phoenix to visit Barrow which does specialize in VM.