Medical Coverage for Dental Work Question

I didn’t exactly know where to put this, and what investigating on the subject I’ve done so far hasn’t been very successful. I figured I’d ask to see if anyone knew about my scenario and may be able to provide some recommendations.

I’ve been working with Dental Specialist for the past year to plan a procedure to correct my teeth and bite on the right-side of my mouth. The work that would go into it would be extensive (teeth removal, braces, implants, etc).

Normally I wouldn’t imagine that this would be something that could be covered by medical/health insurance, but the back story of how these occurred is likely due cancer treatment I had when I was extremely young. I had radiation therapy applied to the upper right hand side of my mouth/eye (I had cancer in my right eye, and this was a treatment method that was applied). Now the current day adult me has an entire section of teeth on the top right side of my mouth that have no roots and are ready to fall out just about any day now, and a terrible bite on my right side caused by the teeth not growing properly. The bone in the affected area never fully formed either requiring the options for dental work to be extensive.

The Specialist submitted a letter of medical necessity to my insurance, but every time they had done so they had been denied for “many reasons.” Now, I’m being told that I have to either pick up the cause and advocate for myself or pay for the whole plan out of pocket which is running well above 40K USD as they’re no longer pursuing this procedure on my behalf.

Is there anything I can do at this point that may be assist in advocating for my cause? The bill is honestly way too much for me to handle, and I’m really trying to not end up with missing an entire section of teeth in my early 20s. Any recommendations/experiences that others could share would be greatly appreciated.