@Melanie1218 it's going to be tough. Not being able to have dairy is not really a complication of gastric bypass. It causes lactose intolerance in many people, as does the DS. So it's not considered a complication, but rather, part of the nature of the operation.
Same for dumping with sugar - that's how dumping works. Not every patient dumps, and we really don't know why some people dump with gastric bypass and others don't, or why for some people it's sugar that causes dumping while for others it's fat, but it's a side effect, not a complication. That is, unless you have abnormal dumping, which does occur occasionally, in which the patient dumps on healthy foods and this causes nutritional problems. But you aren't supposed to be eating sugar after gastric bypass (not being judgmental here, just saying) so if sugar causes dumping, the solution that someone deciding whether or not the insurance company should pay for a revision would tell you is to stop eating sugar.
One of the reasons I think gastric bypass is a flawed operation and could not bring myself to have it is that long term success requires a permanent diet of low fat, low carb and low calorie for life. I knew I would not be able to sustain this forever. I think for many people it's unrealistic. Nevertheless, that's what it takes.
I hope you will be able to get the revision you want, but I think what may prevent approval won't be the bmi of 33, but rather that you don't really have a medical necessity case, unless there is some other reason we don't know about.