Have you ever mentioned to your doctor, in the past, the things you did to try and lose weight? I have BCBS and they had the same requirement. But I had mentioned to my pcp that I did keto, weight watchers, calorie restriction, and the mediterranean diet. When I mentioned this, she put it in the notes that went to the insurance company and they accepted it and that took 6 months off the process.
My pcp was very supportive and was happy for me to do the surgery. I gave her all the requirements from my insurance company (I needed to pass a ekg, her form stating what I've tried to lose weight, my comorbidities, etc...) he jumped right on that and got it done asap.
By the time I went to my 1st appt w/ my surgeon, she had already sent all of this to their office. So I was 3/4 of the way finished on day 1 of seeing my surgeon. All I had left to do was the psych eval, blood work the surgeon needed, and then waiting for it all to be submitted and approved by insurance. My first appt with the surgeon was Feb 28th, 2022. My psych eval was March 7th. Everything was submitted to my insurance on March 10th and I got my approval on March 14th 2022. The longest part of this was honestly actually getting to the surgery date because I couldn't have it until May 3rd due to the surgeon's schedule.
So honestly, the better prepared you are, the more you do behind the scenes, the faster the whole process will go.