Aw, your poor kitty
. What bloodwork was done? Also, did they do a urinalysis? Was a UTI ruled out and were stones ruled out?
When we got Wylie, I also had my beloved cat, Einstein - who lived to be 20 years old. Wylie bugged the crap out of her, bc he was a puppy - and puppies don't really know any better (unless taught) bc they kinda think everyone is their littermate. We taught Wylie the command "Leave it" - which means - "leave it alone" - "it" being anything you need it to be.
We felt we had to step in for Einstein bc Wylie wouldn't back off (being a puppy) and she wasn't very assertive bc she was a senior kitty and her vision was not great. While dogs have a way of working things out (to an extent) amongst themselves in terms of pecking order - I do see a place for intervening when it comes to cats and dogs etcetera, bc dogs and cats have different ways of communicating.
Maybe check out our Training Section and see if there is a thread on the Leave It command...or something similar...?
Or a trainer may have a good way of explaining it here...