Dead mouse update!
Josh found it.
We were headed to the grocery store, forgot something and he ran in to get it. He discovered the cats in the living room, playing dead mouse volleyball. Like, sitting back on their haunches and batting it back and forth.
Which means that they had it stashed somewhere and were just TAKING IT OUT WHEN WE WERE OUT OF THE HOUSE.
I'm now worried that they might secretly be criminal masterminds.