In an open pairs event.
The auction goes as follows ..
1NT = 15-17. W alerted 2D as majors, however E pointed out both diamond bids are meant to be natural after the bidding is done. E/W does not have a fully filled CC.
The hand is played out and the result is 3D -1.
S explains he would be likely to make a negative double and find a spade fit if he knew the diamonds are natural. Also, E had the UI that partner alerted the 2D bid.
Double dummy, 2S is making 3 for N/S, 2H is -3 for E/W.
How would you rule?
EDITED: I do not have the exact hand. E has a 2362 shape, some points and a normal 2d overcall type hand.
Plus... it's free!