Hi and welcome
Sorry you had to come but you do seem to have hit the right place at least with finding an appropriate support group. Pleased to hear you are booked in to see another specialist. Best move is to try for a more definite diagnosis then go from there. You will find the Nortriptyline should help with any chronic pain. Despite actually bring a tricyclics antidepressant it and it’s cousin, Amitriptyline, have been used in small doses to treat any long term pain for decades.
No medics to diagnose on here I’m afraid but whatever the root cause of your own condition back pain can be a result of any vestibular condition if the balance is affected. If your balance is adversely affected in any way your body is thrown out of alignment to some degree and that can cause pain which often occurs in the back, Worked that out for myself years ago. I still get back pain on bad balance days. Of course not being able to stand correctly due to VM makes for the perfect storm because misalignment affects the way the spine communicates with the brain and that can throw the vestibular system into further chaos and we can then become even more off balance. So thinking about it which I’ve not really done ever before, what I’m actually suggesting is the back pain could be either/both cause and effect. Be interesting to hear what the specialist has to say. At least anything visible on the MRI is obvious and should receive prompt attention.
Checked out the archives here and surprise, surprise …. You are not alone, that rarely happens, somebody else has usually been there first!