AETNA PPO IN NETWORK BARIATRIC SURGEON

I am so frustrated tonight. I have waited months to go to the Baylor WLS seminar. I had all my paper work ready and handed it in, listened to the seminar and was so excited. I find out this morning that the surgeons no longer take AETNA PPO because it's considered outside of network and they ask for 6K surgery deposit. So I emailed AETNA asking them who they do my a Bariatric surgeon that is within network. Does any one know anything aboaut AETNA PPO. My husband works for UPS.