Cat has grey poop (already posted on askvet)

I’m an adult. My 11 month old spayed female cat has had 2 grey poops within the last 24 hours. The first one was last night and slightly watery. I looked through it and found a pretty compacted hairball, a mix of my long hair and her short fur. I’m not sure if that has anything to do with her poop colour, but the vet said not likely. The one this morning was well formed but still grey, almost like MacBook color. I immediately called her clinic who knows her history and we were there 20 minutes later. Because she had eaten a little bit in the morning we scheduled bloodwork for Monday, but I took her feces with me and the fast giardia test came back negative, will also be testing for other parasites and blood. They did a fast ultrasound and it showed her motility was slow, in both her stomach and intestines. They gave her anti nausea and pain meds. They are specifically worried about her pancreas or liver, though without bloodwork we can’t be sure.

I am an absolute helicopter cat parent, so I know there are no other visible symptoms. Same activity, same appetite, no dehydration, jaundice, her fur looks the same, her bowel movements happen at the same time but are grey and that’s it!

The thing is, she’s had motility issues in the past that were eventually treated by feeding her a single-protein diet (horse, she wouldn’t accept other “novelty” proteins). She was also on cisapride for well over three months but we stopped that over a month ago (we are supposed to go back on it today). IBD was tested for with a biopsy and endoscopy, negative, steroids didn’t help either. We thought it was a poultry allergy then. The only symptoms of her motility issues in the past were no appetite, which she now had (before the vet visit, she now refuses food and only sniffs it, but it was very normal beforehand, even in the morning before her visit so I hope I didn’t trigger anything and she’s just recovering from the stress). The motility was also visible on ultrasound. I don’t know if this is the cause of the grey poop, or did the motility cause pancreatic issues? What could this motility issue be caused by? Could it just be that she’s like this and just needs cisapride full-time to help her? I’ve had her since she was a week old, her mom rejected her.

Her bloodwork will be on Monday. I scheduled a visit with her gastroenterologist in 10 days, couldn’t do it earlier as she’s on holiday. Is there anything I can do in the meantime? A more specialised ultrasound? Are there any things I could ask about during the next visits? Does anyone have any idea what this motility thing could be?