Misinformation & Serious Error?
E/W have an unopposed auction, with alerts where required:
P (P) !2C (P)
2D (P) 2NT (P)
3NT (P) P (P)
Before the opening lead is faced, N/S ask about the 2NT rebid, and are told by West that it shows 23-24. South leads the H5, and dummy comes down with:
Declarer calls for the H6 from dummy. North (with an 11-count) contributes the HQ from QJ-tight, and Declarer wins with the Ace.
From there, the play trundles along (though neither side could outline how play actually proceeded when asked after the fact, other than it appears to be clear that North did not return HJ at the first opportunity), and at the end, Declarer emerges with 9 tricks. Now it is revealed that 2NT actually promises 21-22. The TD is called, and N/S claim to have been damaged, in particular North states (quite firmly) that "when dummy comes down, and I add those points to mine, and Declarer's 23, I know there isn't room for my partner to have the HK, and this difference is crucial for the defence".
Of course, North has erred here - if Declarer has 23 as stated, there is room for South to have the HK (just).
Have N/S been damaged by misinformation? Or is the error in not adding up to 40 at trick 1 a Serious Error, such that any damage is self-inflicted?
FYI, it was played 5x3NT, 3x2NT, with the number of tricks made varying from 7 to 10 (DD analysis says 8).
 Oh, and PS, if you want to see all of it, it's board 20 here: