Sharon, my pouch does fine with quinoa. I've been eating it for years, in fact before it became an "it food." In fact, very few foods irritate my pouch, per se. The main problem I have is with adhesions at the old stoma site - I have to pay attention to the amount of roughage I'm eating as that's my problem area. But quinoa doesn't seem to cause blockages. I suppose if I ate a ton of it at once, it might, but so far it's been fine. Foods that would cause me issues include things like carrots, raw peppers, green or yellow beans (because of the skins), roasted potatoes (when skins have not been removed), cabbage/coleslaw, popcorn, bean sprouts, stalky Chinese vegetables, salad in excess amounts, and basically any other raw veggie in excess. I expect mushrooms would also give me major issues, but I've never liked them and so don't eat them anyway.
Oddly, though, things like tomatoes and cucumbers usually don't bother me.
But really, I'm actually quite lucky. Despite the problems I've had, my pouch itself is has excellent function and is generally well behaved. My issues have been with adhesions above the pouch, and with the staple line below. Go figure. LOL The pouch was a little angry at me over Christmas, but I indulged in foods I wouldn't normally (lots of sugar, but mainly it was just excess volume! I ate more than my system has been used to in quite some time. My pouch didn't necessarily appreciate that. ).