Thanks for sharing this data - it’s great.

It actually makes sense; if cat urine contained ammonia the smell would be gone once you washed your cat’s impromptu litterbox, since ammonia is both volatile and highly soluble. And yet it keeps stinking - this hints that there’s something else there producing that ammonia by decomposition. (Probably proteins. Cats eat a lot more protein than we do.)

Note: chlorine gas is the one that leaks from an open bleach bottle, and gives it a distinctive smell. The ones created by reacting bleach with ammonia are chloramines, considerably more poisonous.