I'd do the following things:
Un-tilt the cage and don't keep flooding the bottom.
What's the ventilation like? You'll need fine mesh at floor level!
Use a substrate like vermiculite (which holds humidity) and spray lightly and regularly.
Move the heating equipment to one end of the cage.
Add sheets of eggcrate, stacked upright, for hiding spaces. Stack them upright so that the frass falls to the floor.
Stop feeding them meat and cheese - THAT will be what smells. Not just the rotting food, but also poorly digested stuff in the faeces.
I feed my roaches (three species at the moment - dubias, red runners and hissers, although I have kept lobsters as well) a mix of the following:
Sliced "Fresh Greens" (also known as Spring Greens or Collards)
Thinly sliced courgette (zucchini)
Thinly sliced apple
Thinly sliced carrot
They also get a tablespoon or two of moistened chicken layer's mash on occasion for the calcium and protein content.
I suppose the occasional VERY dry cooked chicken bone - with very little meat left on it - or a little bit of dry cat food or undyed dog food - would be suitable as well, but I don't use it myself.
"My bum has been a bum for a very long time, but that does n't mean I have to listen to what it says."
- Terry Pratchett, Fifth Elephant