How mucked is too mucked?

[whorasaurus]

Here's a good one. Two old guys go at it at 1/2. Bet, call, bet call, bet call. By the river, the board is 3 flushed. Old man #1 (who called river) asks what Old man #2 has. Old man #2 replies, "a flush." Old man #1 mucks his cards face down in disgust. Dealer makes Old man #2 show hand, which is KQ offsuit (no flush!). Old man #1 leaps into the muck and gets one card that was certainly his (not deep in the muck), and cant find his other one. Problem is, the one card he has is an ace, which pairs the board and is the best hand.

If you are floor, what do you do?