It's a rat pink, not a pinkie mouse.
To the OP: I wouldn't worry too much about it. If it's still alive, it won't be much longer. And a rat pink really can't do any harm to your snake. He should be just fine. But if he eats that willingly, perhaps you should try feeding him frozen/thawed. That would eliminate the problem of it still being alive when he sucks it down.![]()