I first give you the South hand.
My view: S has shown a preemptive bid in diamonds, N has said that opposite this preemptive bid in diamonds he would like to play 4♥, and so the natural call is a pass.
However: the 4♦ was alerted at the time it was made. After Pass-4♥. E asked fr the meaning and it was explained as diamond shortage and hear support.
Question 1: I am pretty sure that S must still pass, am I right? I cannot see why he would bid 5♦ if he believes that his partner understood his 4♦ bid in the way he intended it, so the only basis for 5♦ would be a belief that partner had a different understanding of 4♦ then he intended, and he knows this from the alert, not from bridge logic. Right?
I am assuming I am right so far. But next I believe i made an error.
Question 2: S did bid 5♦ and I (I am West) summoned the director. I have seen this movie before and I am tired of it, but in theory this could all be legit. So the question is: Just when do I summon the director? I am pretty sure that I did it too soon, but I fear it will go Pass-Pass-Pass and then we eventually learn that S has long diamonds and we have to try to figure out what should have happened.
Ok, now the full hands and the full bidding.
Off 1, good enough, so I am not stewing all that much. He has 7 diamonds tricks, 2 side aces, a club ruff, and he can establish a long heart. Nothing to be done about that.
There was a 5♣ contract our way, making, I have no idea how. There was a 3NT by W, making, which it does unless N starts with the ace and another diamond. I doubt we can hold 4♥ to three tricks, and 4♥, undoubled, down 3 or 4 or even 5, seems to be the same matchpoint score as 6♦ X down 1.
Had I not called the director when i did, I don't know if 5♦ would have been passed. The pair is not a regular partnership and I can imagine N wondering why on Earth his 4♥ has been pulled by a partner with no aces outside the trump suit and then placing a bet that it is because 4♦ showed diamonds. My objection was much more to the 5♦ call than any hypothetical Pass by N, had I just quietly passed the 5♦
So: In addition to questions 1 and 2, suppose I had kept quiet and suppose 5♦ had been passed out, making 5. Then I summon the director. The ruling would be?
Comments beyond my questions are welcome. This problem is more common than I would like it to be and I wish to deal with it correctly. As S, I would pass partner's 4♥ and I assume we are all supposed to. But it does not always happen.