I used nemsis odour neutraliser for the first time today and was impressed!
For strong dog smells I'd pre-spray with hot enz-all from chemspec (this enyzme boosted pre-spray should remove the smell on its own!), agitate, let dwell and extract.
Then once all the main crap has been extracted, apply nemsis by sprayer and let dwell for 10 minutes before extracting (or you could just leave it at that.
From my experience I hardly think a dog smell will have affected the underlay doesn't matter how strong the smell is. Unless the bugger has pee'd on the carpeto of course....
For urine, i dont experiment!! Urine contamination treatment from ChemSpec everytime baby!
Then of course, after you've been paid kill the dog on your way out
Tony