Rules (OTB) question - last move when partner is checkmated

Yesterday, we had a situation OTB where I checkmated my opponent sacking a Q, but my partner got mated with that Q. Initially my partner's opponent put it on one square where it would have been m2, but he didn't finish the move. Then after few seconds he noticed a checkmate in 1 on another square and put the Q there checkmating my partner. It took maybe 3-4 seconds for his last move. So, my actual question is how much time does one can take for his last move when his partner has just been checkmated. Can I sit for all my remaining time searching for m1 and if I find one, will it be a draw? Will it still count as "both games finish at the same time"

I think online, of course the side which checkmates first wins.

And OTB, I think this is the same - the case of a draw because of two simultaneous checkmates would be only for cases in which the first checkmate has not been clearly noticed before the second checkmate happened, so that it becomes unclear to tell which mate was first.

So I would imagine that if you call "mate!" when you give mate yourself, it will be easiest to tell that it is faster than the "mate!" from the other side a few seconds later. (Just as calling "time!" is the way to be first as compared to a checkmate on the board - if your opponent's flag has fallen before he checkmates you.)

This is how I would think that the order of "which checkmate was first" can be determined OTB.

However I do not know about the detailed official bughouse rules for this, or possibly which local versions of them will make which official difference in detail.

There are no official bughouse rules. I am playing it if there is m1 at the other board with the incoming piece it's a draw. If not given right away it should be a loss.

I think there are quite some tournaments offering bughouse having established some rules that could come pretty close to being some "official" rules.

example:

http://www.czechopen.net/en/festival-tournaments/l-bughouse/rules/

These rules have

I would think I can recognize some logic there:

If it is feasible to tell which mate has come first, then the first mate should win.

Online, it is feaible ... the server software will decide it automatically.

OTB, the arbiters may usually find it hard to decide in split second difference cases which mate on which board was first. This may be one reason for the rule allowing the player on the second board to at least still make a move with the piece that had just been captured on the other board.

So at least according to the official rules of the Czech Open, the case of the OP mentioned above is indeed a draw, because the player on the second board was allowed to still make a move dropping the queen that had just been captured.

OTB, i would declare it a draw.  If you take a piece for your partner, which allows the partner to mate in one, but you also get mated in one, that should be a draw, and it shouldn't matter "who clicked first"

In the Czech Republic we have official bughouse rules approved by the Czech Chess Federation.

https://www.chess.cz/sachovy-svaz-cr/legislativa/pravidla-bughouse-sachu/

http://bughousechess.wz.cz/CompleteBughouseChessRules.htm

Ok, thanks. But what if you can find m1 not with the captured piece using all your time - does it still count as draw, or should it be done with a captured piece only?