What is the best thing to do at this point to get my insurance claim covered?

I have very bad TMJ (otherwise known as TMD). My jaw is clicking, it is painful, I am having chronic tension headaches and for an already chronic migraine sufferer I am not able to fully function anymore. I have not ate a steak or chewed gum in over 2 years due to this. My jaw in the last few months has gotten horrible. Went to a chiropractor recently and they were shocked of the state my jaw was in. I have had this problem for many years and back in 2015 went to the one and only TMJ oral surgery place within a 50 mile radius. They made me a splint and the splint did not work. So then they at that time said what do you want to do and I said nothing at that time and just leave it because at that time it was not as bad as it is now. That oral surgery place only does surgeries on wisdom teeth removal they no longer do the TMJ surgery. They refer to the nearest TMJ clinic which is a state university over 120 miles away. So I contacted insurance and they said to have my MD (general practitioner/family medicine doctor) fill out a prior authorization to get insurance to cover me to see this state university which can do surgery.

Fast forward 2 weeks later back in July 2024 and they denied the prior authorization stating I needed to go and see the oral surgery place nearby I had already seen. I called the oral surgery place and they outright refuse to see me because the furthest they go for treating TMJ is making the splint. I ask my doctor to submit another prior authorization detailing for sure I have already been seen by the oral surgery place and I cannot return and explaining why. Insurance sends another prior authorization denial with the exact same verbiage as before stating I need to go see the oral surgery place I had already seen years ago. I am up in arms. I feel like I have a lawsuit against my insurance company. How should I proceed at this point? I think I need jaw surgery immediately.