With every insurance plan, you have a right to change doctors
and you have a right to a second opinion.
If necessary, call Legal Aid and have them contact
either your ins co or your doc (or both),
and threaten them with whatever your state law says you can do.
The teaching hospital is an excellent idea- look for one with a large neuro dept, and as a bonus find out if they do research in neuropathic pain. That's your best bet, and I'd wager that
the 'county' plan accepts local hospitals' billing.
Ask for a list of acceptable hospitals in your area & plan. Work from there.