Rare, but not unknown with the younger balls.
True, that much more difficult to digest a reptile than a bird or rodent. Where will be critical, when he already digested partially, but the process not enough fast, and the little girl start to rotting in the stomach.
If he'll survive that accident, in your place at least 3-4 weeks I skip the feedings.
It happened for me with a young T.albolabris pair, and the two snakes was the same size. For them, cannibalism is much more common. Wasn't funny...