A.,
My first thought is why the HECK would you hide a toy in a room that she's constantly in? I don't see how your husband is the idiot here, when you posted that you constantly have to chase your 4 year old out of that room.
When we've done things like this I've hidden them in the very back corner of my bedroom closet shelf, wrapped in multiple bags from various stores. Or, I hide it under my bed near my nightstand. Or, in a dresser drawer under all my clothes. Or, in another house altogether.
I think on this one you both screwed up and placed the coveted toy somewhere easy for your daughter to find it.
All that being said, there are a couple of games hardwired into the system that she can have fun with without any game cartridge installed.
Kindly,
Melissa