Got precert now not sure--fund office acting nasty

Hi. I have been given precertification stating it is medically necessary for me to have the surgery. I then called my husband's fund office (he works for UPS, is with teamsters local 639, and has Cigna PPO with a fund office who administer the benefits from what I understand) and was basically told she wasn't sure about what they are doing with gastric bypass claims because it is in review. She also said that it isn't a covered service. I told her that I was told in a few different calls to them that it is not a covered service unless it is medically necessary and I was told they have paid claims for gastric bypass before. I also told her they can't just arbitrarily change how they pay gastric bypass claims in the middle of a contract period.  I did have some people at the fund office tell me flat out it was not covered at all though, so I don't konw what to think. Unfortunately, all I have in writing is the policy that says treatment for obesity is a noncovered service. It was explained to me (again just on the phone) that when it says that it means things like weigh****chers, etc., and gastric bypass treats the comorbidities--not the obesity per se. I am just hoping I got a nasty grumpy lady and that all is well. Another lady told me the same day when I called back that normally if precertification is given then when the claim is submitted it is paid. That is all fine and good if it is normally, but I am terrified to go into surgery without something in writing or some proof they will pay, especially if my claim may cross the desk of the hag I had to deal with today. They have just been too wishy washy up to now. Any thoughts on this whole thing. I can't get a manager on the phone until next week. Should I just do the surgery and fight it later if they deny it? Can I fight it later if they deny it? How on earth can the employees tell me that it is covered if medically necessary if it isn't true? UGH!! Thanks for any help.

Denise