medicare requirments

I began this process last week when I attended Tampa General "A Center of Excellence" which Medicare required. At that meeting I was told I would have to be on a weight program under a Doctor for 18 months and these first meeting would not even count because I must attend them with in 12 months of my surgery. When I returned home I began looking up the requirements of Medicare on the internet. I was not able to find the 18 months any where it did stat the 6 to 12 months seem to be reasonable but not necessary. So I called Medicare and after an hour and being transferred to 5 different people to get the requirements. I was told they would send them to me in 10 to 12 days. I asked the woman how long of a weight study did I have to have and she said 4 weeks. No sure what the requirements are can anyone help me with these requirements. I have an appointment with Lee Memorial Hosp in Fort Myers where I live that my Dr. recommended. He said they did everthing for him in the past. I talked to them today and found that they have a nutritionist working for them but not a Dr. Will this be ok. It will cost me $270 for the program. I am to start Friday ??? Should I start this?? As you can see I AM NEW AT THIS AND FLOUNDERING,PLEASE HELP.