Problem more than anything

I understand that BC/BS PPO covers some weight loss surgery, but somehow, my husband's employer, is denying coverage because they say they are exempt due to ERISA from covering this surgery???? I then called customer service at BC/BS and they indeed verified it. I know at one point my husband's employer was self-insured because they had so many employees. My husband is a truck driver by the way so any truck driver's or wives who can help me...please email me because I'm stooped as to what to do?? Anyway, they recently changed insurance companies last January and went from a self-insured plan to a BC/BS PPO plan, but apparantly they're still covered under the same exemption? Help??? Anyone? The company is Marten Transport out of Mondovi, Wisconsin. Thanks. Dawn