Unsolicited reply guy here. If you have scapular winging involved in your thoracic outlet syndrome, tight levator scaps can cause kind of a migraine headache feeling where it reaches up the back of your neck. I've run into it with clients before. DM if you'd like helpful links. Sorry you're hurting!

Thank you so much for the list! This makes the migration a little easier for us new folk slowly rebuilding our timeline.