I would think that the only way to make ANY sense of the situation is for the woman to repeat back to the croc EXACTLY what he said to HER: "If I guess right, you'll give my baby back, if I dont, you'll eat him. That's what you'll do to him." He'd have to return the baby, because she's CORRECT NO MATTER WHAT. Eh? hehehe
I think this is a reasonable answer.