I wouldn't. The only time i'd put it back in the freezer is if he refuses, and then I put it in the freezer immediately. Letting it sit over night gives it time to start breaking down, and by the time you leave it sitting for a few hours, refreeze it, then thaw it, and attempt again...it can be a pretty nasty smell, probably began to rot...which is not a good thing to feed to your snakes.