@SadieM1210 strictures are typical for a Crohn's. Perhaps that's why she thinks so. Your stricture is treated with endoscopic balloon dilatation for several months now. So there must be quite a bottleneck at your pouch inlet. Your CT scans should tell how much diameter is left and how long the stricture is. Do you know? Has dilatation been successful so far?
If that stricture is the root cause for your problem with having regular BM then I would agree to Kushami that a low residue diet would be better, anything that does not bulk up your stool and lead to a near obstruction in upright position. Unsoluble fiber produces bacterial fermentation processes at the end of the digestive tract. That promotes gas problems.
You may try and prove that your stricture is causing those problems if you stay on a fluid diet for several days. Get yourself full caloric fluid nutrition for replacing food, drink enough additionally and see if things clear up and you can have BM on the toilet.