Ruling on suited pairs

[SkiGuyGT]

At my work we have a cheap NL cash game we play on breaks. Anyways there was a hand where one guy got a card from the 2nd deck we were using and floped a suited pair of queens. Well he made a flush on another player on the river which I suppose you would call a double queen high flush? Well when we all noticed this he of course wanted to keep the pot but the loser wanted to take back his share. Anyone know what the ruling on this situation would be?