Prior auth denied for a surgery my doctor says I urgently need. What exactly is my appeal process?

My orthopedic surgeon has recommended a rotator cuff repair surgery for me. I've had two cortisone shots, done six weeks of physical therapy, and the MRI shows a complete tear. My surgeon submitted the prior authorization request with all the documentation. Denied. The reason they gave: "not medically necessary" and "conservative treatment not exhausted." I've been in daily pain for four months. I've done everything they asked. And now they're saying it's not necessary.

I'm trying to figure out the actual appeal process here because the denial letter is full of insurance jargon and honestly I can barely follow it. It says I have 180 days to file a first-level internal appeal, and after that I can do a second-level appeal, and then something about an "independent external review." I don't know how realistic it is to fight this, what information I actually need to submit, or how long all this takes. My surgeon's office said they would help with the paperwork but they seemed pretty overloaded and I'm not sure I can rely on them to carry this.

Has anyone been through a prior auth appeal for surgery specifically? What made the difference in getting it approved? I'm also wondering whether there's anything I can do to speed this up given how much pain I'm in - I've seen people mention something about an "urgent" or "expedited" appeal process but I don't know if that applies here.