I would just charge them for everything and make sure to give them detailed receipts…
Having been a renter before, I agree that hiring a professional “crew” is the best idea. In my last few rentals, I cleaned absolutely nothing and still got a decent (nearly all) of my deposit back even if charged. It doesn’t seem to cost that much and they do a much better job and is less stress.
For college kids, since they KNOW they had a dog and smoked, you can state that you aren’t even billing them extra (unknown made up comment) for the extensive smoke and damage and just charge for cleaning and here are the receipts…
They would probably just blame the guy who had the g/f over with the dog and smoked and fight over the deposit since they know they did it amongst themselves. Since you’ve warned them before and have receipts, it sounds like this is pretty to me…
especially since you ARE spending the money on getting it back into rental shape and aren’t pocketing the money.