Well, in that case... The guy who bought the coffee threw the cup away, relinquishing any claim to a prize. If he was too stupid to check for a winner, then he is too stupid to win. Therefore, the girl who retrieved the cup, through her parents, is entitled to the prize. For helping her unroll the rim, the 12 year old should receive a thank you. If the first girl's parents decide to partner a thank you and a check, that is entirely up to them.