Try adding a bit of citrus peel in amongst the compost. I'm sure a bit will not turn it acidic and i would like to know the results. If the cats have peed they will be back, unfortunately. It is up to you if you want to try the Jeyes fluid on a tea back trick. i know it works but it has ethical issues that i do not want to get into, but they have been mentioned on here, on other threads.
If they are raised beds you could try the Ralgex along the edges and see what happens. I have not tried this and can imagine that it will have to be done often in this wet weather. The only other thing that i know works is the Scarecrow sprinkler system and i think it is one of the best but you have to pay. Try a citrus spray round the edges?
Please let us know how you get on.