I hear your frustrations, . It sounds like you've tried many, many things to try and resolve your migraines. Has your neurologist made any recommendations on what you may have not tried? My fear of piling on more suggestions is that they may have been something you've already tried. Only you and your medical team know the true extent to which you've covered your bases.
I would say the most infrequent treatment I have seen is the use of neuromodular devices. Here is a link to some examples: https://migraine.com/devices. Anecdotally, others have reported using something like the Reed procedure to reduce migraines. However, as I'm not an expert in migraines, I can't provide any guidance as to if you'd be a candidate or if it would work for you.
Wishing you well, and hope that you will find a path forward to resolving your migraines soon. - Cody (Team Member)