My first 2 of my current hatch got out of the shells, fine, all the rest so far have been 'assisted births'. Maybe I should have let Pixie the cat come in to help like she wanted to...
Cats just love to get on top of things, especially warm things. "Oh look, what a perfect spot for a nap..." I have to be careful with trays of seedlings, too, I have one cat in particular that will climb into or onto anything that even vaguely resembles a box. Even if it's a little bitty one that she hangs off of on all sides! It's a fixation she has, with some very silly looking results. Picture a 15 lb. cat curled up on a box about half her size...I've seen her try to curl up in an open egg carton.
I keep my 'bator in a room I can keep the cats (and dogs) out of. Until I build a cabinet type that won't get knocked over, anyway. Confining the 'bator's easier for me than confining the cats! It doesn't care if it's isolated in a room!