Oh What a cat. Is he still alive?? (hehe)-not relagated to back porch?? Only thing I found that works taking odor out is baking soda and water. I'd put the peed spot in a plastic container after filling with warm water and lots of baking soda, dissolved in the water. Leave it there till fibers are all soaked, maybe an hr? or 2? -maybe to long,--guess you would need to take it out and smell if smell is gone, or needs more soaking time.
I've had success putting in washer just with maybe a 4th box of baking soda and let run through cycles. If really strong, maybe needs second go round.