Orange peels. Cats don’t like the scent of citrus, so a few peels sitting on top of the soil might work. (I say might because cats are weird and I’m certain there are some wee beasties out there that like it, so…your mileage, etc.)
And not just UTIs. Any toileting outside the box needs to be addressed, as cats are very good at hiding when something is wrong (instinct from being both predator and prey). I have a cat with anxiety and that manifested as peeing on the floor.
The painted claws were a bit of misdirection while Eight Ball disappeared.