I am chiming in here a little late You've gotten a lot of good advice, and it should be clear by now, every case is different
Fletcher's my IBD dog, he's been on raw for the last 5 yrs. I found out what he could tolerate and what set him off by trial and error. Once her UTI clears up, you'll really be able to tell what works for her. Keep it to one or two things, that makes it easier to see if something is causing a problem. The main problem with kibble is that most of them just have too many ingredients.
I wouldn't scope except as a last resort. Raw, cooked, commercial, home-made, fish, beef, chicken, lamb, grain, veggies, any or all of these could be the culprit . Among other things, Fletcher can't have molasses, who would have thought?
It seems to take forever, but you can figure it out!