I am looking for someone who had gained quite a bit of weight after having had the bypass surgery and successfully re-lost all the weight and what program or diet they used to do this

I haven't but I know a few people who have. Some went back to basics (not all the way back to liquid diet and protein shakes, but (dense) protein first, then non-starchy veggies, and then, if you have room, a small serving of fruit or whole grain carbs). They also lowered their average calorie intake a little every week or two until they found a level that they'd lose weight at. There are also a few who did Weight Watchers.