Jules, the stretching that the surgeon is referring to is likely whether the remaining intestine will reach the lower pelvis after the failed pouch is snipped off the end. As long as they don’t pull it too tight, impairing the blood supply, it would likely work fine. They would have to have your permission to explore that option during surgery. It’s uncomfortable to enter surgery without knowing exactly what will be done, but sometimes that’s the only way to get the best possible result.