Oh as far as getting the smell out of fabric who ever mentioned the product to break down the uric acid has my vote. Vinegar may help but it won't do a really good job and I hope you used white vinegar it is better for cleaning than apple cider vinegar. Fabrize will just mask the oder and eventually it will come back especially on a hot humid day. Plus you run the risk of the cat re-using that spot to potty again.
Another idea is you might want to take it to a professional dry cleaners they probably have a good remedy for cat urine.
Why don't you keep the cats outside?