Well, I ended up pre killing (or maybe post killing depending on how you look at it) the mouse, and left it in his tub while we left for our family Christmas party. I was thinking about it during the entire party, and told him before we left "All you need to do for Christmas is just eat that mouse Wiggles!" Came home from the party, changed clothes and eagerly checked if the tub was empty... IT WAS! So now he's got a full belly, and a very happy owner, once again.
I guess everyone has to have a picky eater. So far, he's been it! Now I'm curious as to how next week will go...