The results were still not very conclusive, though. The dye largely moved through the intestines with no obstruction, but the stomach just looks...abnormal. Maybe some of the fabric covering from the coiled toy, maybe something else. But whatever it is seems to be irritating him, and causing the vomiting and lack of interest in food.
Bottom line: the vet will operate tomorrow morning and try to remove whatever it is. Fish will spend tonight at the vet's, and will be first up for surgery. Please send your good luck and fast healing vibes this way!