A Tragic Switch

Eight minutes into round five of a PTQ, you are called over to tables 35 and 36.

Albert and Yuval are sitting at table 35. Albert has just won a game, and they are just presenting their decks after sideboarding.

Bob and Zachary are sitting at table 36. They are in the middle of game one.

They called you when their results slips arrived. Upon looking at the slips, they realized Albert and Bob should have been playing at 35, and Yuval and Zachary should have been playing at 36.

They realize things aren’t what they should be, but they start arguing that they couldn’t know earlier that they were at the wrong table since it took sooo long until the result slips finally arrived. What do you do? What are the relevant infractions, penalties, and fixes, if any?

Judges, feel free to discuss this scenario on Judge Apps!

As many of you pointed out, playing the wrong opponent is an explicit example of IPG 3.1 Tardiness. Since this was discovered before the 10 minutes limit announced for Tardiness (as it usually is 0/10 for PTQs), Bob and Yuval are each going to receive a Game Loss. The existing games/matches are not part of the tournament and thus do not count so both matches are immediatedly stopped and any result is voided.
Since no official games have been completed (or even started), the Game Losses are applied immediately and Bob and Yuval go to play their own matches at the appropriate tables.

To fix the situation, seat the players correctly at 35/36. Bob and Yuval are both down one game, but will have the choice to play or draw for game 2. None of the players may sideboard for game 2 (so Albert and Yuval have to de-sideboard their decks). Give each table a time extension equal to the elapsed time in the round, which means 8 minutes in this case plus your ruling time so that they have the same 50 minutes for their matches as all the other players have.