2N was not alerted and is on the card as natural 10-12/11-12 bal
N said he thought he was making a forcing bid.
**edit he actually bid 6♦ over 5♦ **
EW contended that N has UI that his partner had bid 5♦ over an inv balanced 2N so is now showing more than he would show over a forcing 2N which would be a 10 count with 7 diamonds.
It gets worse:
Declarer had:
The opening lead was a spade to E's ace and declarer's K (should play the Q in case E tries to cash another) and now E is trying to find W's ace. E can see the missing trump so a heart return pretty much can't cost given the auction, but E returned a club and the heart went away on ♠J.
Any suggestion how you sort this out ?