The "surgeon working with the insurance" you mention is your surgeon contacting the insurance company on your behalf and explaining your individual situation. Typically the doctor's office sends in a request for pre- approval of the surgery. If the surgery is denied, they will state the reason. At that point, your doctor would contact the insurance company to explain why your case is "medically necessary".
If your pre-approval is denied, I would contact the insurance company myself and find out what steps I needed to take to get the issue reconsidered- second opinions, etc. Offer to go to a doctor of their choosing. Keep notes on all calls you make and whom you speak to.
Your success is going to depend largely on you and how you've presented yourself so far. Is your motivation to look better or to improve your health? Have you tried everything the doctor has recommended so far? Did you first come to the doctor because of pain or because of your appearance?
Best of luck to you.