West open 1NT, North overcalled 2D, East bid 4H. At this moment, South said, "ups, I must alert 2D". East asked and was informed that 2D means an overcall with one unknown major (multi-landy). He said he mantain his 4H and he didn't called TD. The bidding continued with p-p-p.
The explanation was correct and confirmed by CC. It is in fact more frequent that 2D means "multi" rather than natural (with diamonds) for players in this particular context (country, skill, experience etc).
The play started with spade lead and declarer went one down (losing 2 spades and 2 clubs).
After the play, declarer called TD and said that lack of alert (or the late alert) prejudiced him. "I can make 3NT. if i knew what 2D is, i'll pass and then after the presumed 2H in South and 2S by North, revealing the major, I can continue with 3S to ask partner for stopper and we'll play 3NT".
TD adjusted the table score from 4H-1 to "50% 3NT= and 50% 4H-1".
All the players are experienced, S with ~ 15 years, E with ~ 30 years of competitive bridge.
NS appealed considering that
1. E may have called TD when was informed about what 2D is and changed hid call
2. the explanation about how to reach 3NT are not very believable (never showing the heart suit etc).
What would be your decision in this appeal?

Help
