It can happen but really uncommon. BPs don't naturally prey on each other like kingsnakes do. If it were a kingsnake, a ratsnake, or even a garter snake, I would say yeah it probably ate it, but BPs I really doubt it, he is probably just freaked out hiding somewhere. He is going to stay hunkered down during the day and come out at night. I actually have a protocol for escaped snakes though I have never had to use it (knock on wood) I'd get rodent smell all over an electric blanket and put it on the floor in a heap, plugged in, overnight. The heat combined with the rodent smell should attract him fairly quickly. Don't do this with a UTH because it will burn him. Best of luck to you.