I think this is a simple GPE - GRV - Warning for incorrectly resolving a spell. I would have the player randomly put a card on the top of his library.
That's a tough one though, would you put the card on top or bottom? I think the player clearly wanted the card to go on top, but brainfarted and put it in his hand instead. Yeah, I think I'd put it on top.
EDIT: Looking back at the other responses, I disagree; this is not DEC. If he had put the card strait from the library to his hand, then yes. But he started resolving the Scry, IE he looked at the card. As trifle as that sounds, it makes all the difference.
Edited Sal Cortez (Sept. 10, 2014 03:21:11 PM)