ok hun…right…leather is very absorbant…it’s the type of tanning and the finishing products used on it that makes it waterproof…furniture leather is not of course waterproofed in the same way as leather to be worn…i would guess that the urine has soaked through somewhat…and the smell is stimulating him…normal neutralising wont work…what i suggest you try is…wash it with what you been using…then when it is dry you need to get a good layer of old fashioned wax on it…the stuff in a tin…or use the wax horse folk use on their leathers…add a little clove oil to the wax…do underneath and the feet too if it has any…and both sides of the cushions…then put him out and spray with a neutralising air freshener…
try that 🙂 good arm exercise…all that elbow grease 😉