OMG the nose blindness was worse than I thought!
In a fit of productivity I ripped out my breezeway carpet. 40 year old nasty grey cheap carpet. It was so old and degraded that the glue it had been laid with was dust. it just peeled right up.
And dear god the smell.
Old lady cats do such very very bad things to carpet when they get pissed off... Apparently despite a lot of cleaning this was a world record of stench. I feel bad for the neighbors as it is still sitting by the road polluting the whole neighborhood.
But back to the breezeway. After some soaking, scrubbing, scraping, mopping and hosing I painted it a cool blueish grey with some Oops paint I got for $12. Concrete paint of course, you cannot use regular paint on a floor...
After a couple coats it is like a beautiful miracle in there. The concrete is now sealed and pretty! Cats have a little cooler room and most importantly the STENCH is gone.