Any rodents one BP doesnt eat get offered as a second meal to the others, if it is still not eaten I re-freeze it. You have to re-freeze because otherwise it'll just decompose. Try to feed, if it refuses, re freeze. Thaw it out the next week for feeding time, if it doesnt get eaten...flush him. No other way about it really I think.

And if you cant keep it in your fridge you might as well chuck it dude.