Need Input On Gastric Sleeve Surgery Denial

A quick background - I had a lapband slip diagnosed in June. EGD confirmation in July. Band removed in September. And last week my insurance denied my revision to a sleeve. I have a background in the insurance industry so I'm not completely at a loss, but... My surgeon had a wonderful lady who knew the revision process inside and out, who quit just a few weeks ago. Their new lady is, well... new... and I'm her first revision case. Uh oh. So I'm kind of having to be my own advocate, because she just doesn't know. The reasons for my denial were:

1. Failure to submit proof of a mechanical failure
   
2. Failure to document proof of adherence to the prescribed diet and exercise requirements.
   

The revision is covered, otherwise. I don't have to worry about exclusions. But I need to figure out how to prove those two points.

1. Mechanical failure - my insurance company (Cigna) does include a slip in their definition of mechanical failure, and both my x-ray and EGD report were provided. Does anyone have any other ideas how we can document or prove mechanical failure other than those two things? I'm not sure what else I can give them, unless I have the surgeon himself write a letter confirming it.
   
2. First, lap-band doesn't have a prescribed diet. It's a restrictive procedure. I'm not sure I can prove compliance with a prescribed diet when there really isn't one. I have no way to document portion enforcement. The best I can think of is to gather medical records from doctor's visits (other than my surgeon's office), that demonstrate a steady loss or maintenance until when I had my daughter (I gained in my last trimester, then lost all but about 10, then gained about 20 - right around the time I started showing symptoms of what ended up being a slip). But even with a slipped band/lack of major restriction, I maintained for about 2 years. My surgeon's office wasn't sure these records would do the trick. I know I have OB records that will weigh me in at least 150 lbs down from when I first had the lapband put in.
   

Anyone experienced denial on these same two provisions? Would you mind sharing what types of information & documentation you provided?

Thanks all... I'm an instant gratification kind of girl, and this blows.