poop is always going to stink, nothing that can be done about it, other than cleaning it up as soon as possible. Improving ventilation in the room the dragons are in will help reduce the build up of odor, and air filters can help clean the air but in the end, cleaning the cage is still the most effective thing to do.
Avoid using any scented air fresheners around the cages though. These things may be harmful to dragons to inhale (they certainly are harmful to me to inhale...all those plug in oil things, potpourri etc. just burn through my sinuses like I am inhaling glass shards, not to mention if strong enough making my eyes water and my throat burn. Poop, though not pleasant to smell, just smells bad to me, doesn't have the burning watering sensation perfumy junk does (most often, it just ends up being a poop smelling and burning floral crappy perfume scent all blended together anyway...so I get the worst of both).
If your dragon poops while you are not there but your significant other is, and she doesn't like the smell, she can always go ahead and clean it up and when you get home, thank her profusely for being so helpful 
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PHLdyPayne