Occasionly contestant A will give their question to an answer that is initially ruled incorrect. A minute or so later Alex comes back and says that answer was indeed correct and gives credit to Contestant A for the money he/she lost plus the money that the question was worth.
Meanwhile, after Contestant a gives the “wrong” answer Contestant B chimes in and correctly gives the right question and gets dollar credit.
Question 1: Does Contestant B ever get money taken away because Contestant A had the right question?
Question 2: Since contestant B gives the right question he/she gets to choose the next answer on the board. It is one of the daily doubles. If contestant A was given credit for the right question he/she could have picked the daily double. That could have a big effect on the outcome of the game. Are their rules that cover this circumstance and Contestant A is just out of luck?
personally I have never seen a judgement take place AFTER the next question has been picked. I believe at that point any “play” on the previous question is void.
The answer to question 1 is no, they don’t take money away from contestant B. It was their mistake, s/he’s not to blame.
Question 2 is more interesting. I don’t watch the show enough anymore to know if it has actually happened, but I can tell you that they have a rule that says the decisions of their judges are final. So they could just say, Lump it.
But they have on occasion brought people back for another chance if an error was discovered after the game was aired, so that option exists.
But I think they probably wouldn’t do anything. The fact that a DD was out there and happened to be the next one picked by Contestant B doesn’t mean that it was inevitable that Contestant A would have picked it. It’s just one of those things.
I saw a episode the other night, I think it was the college or maybe teen tournament. One of the contestant A gave an incorrect answer, constestant B then gave an incorrect answer and contsetant C answered correctly.
After the commercial break Alex came back and said that the answer A gave was accpetable and gave the money she would have won. He then went to B and gave back the money he lost - because he never would have been able to guess if the judges had ruled correctly. Contestant C got to keep his the way it was…
I thought it was kinda strange at the time…
A player can NEVER challenge Alex or the judge during taping. During breaks, a player may make his/her challenge. If it is accepted by the judge, the player will receive the money but nothing else. No money is deducted from any other player. No change in the player picking the next category.
This rule has been consistent since around 1990. There were slight variations in early seasons.
The show is heavily editted, right? So, they have time to challenge, and adjust, but the home audience doesn’t see that.
They do commercial breaks in real time unless there’s a problem, as I recall, or at least they did about ten years ago, when my mom was on. Except for the break before Final Jeopardy; they give them all the time they want to figure out their math.
But yeah, game shows are heavily edited. I once sat through an awful 20 minutes at a Price is Right taping when a new game (which was subsequently retired!) was malfunctioning left and right. When I saw the aired show, you would have never known there was a problem. Simply amazing. That show is done in realtime, too, and I’m very impressed with their production people.
The show is done in real time except for problems, challenges, and before Final Jeopardy.
We hit a snag when I was on. There was a video category that the video never came up on, but I answered the question anyway (it was an easy one). The edit was done while I was standing there. They essentially made the video question a regular question, and then resumed play.
I came in second at the end. Good for a week’s stay in Puerto Rico. We used it as our honeymoon. 
Are you sure about this? There was a 60 Minutes not too long ago that showed how a dispute on an answer resulted in like a 30-minute pause while the judges called some professor of somethingorother at such-and-such university. It was quite clear from the context that this was not an extended break where a commercial should have been, but a pause that would be edited out during questions.
However, I don’t recall that the program showed how the challenge started- whether the judges began it themselves or whether the player said something.
My mom tied for second and got a trip to Ireland. Nyah nyah. (Oh, I wish I could have GONE! I’m still jealous.)
A bit off topic, but I’ll probably never get to use this anecdote again.
On “Millionaire” once, someone had a question about the term “iron horse.” The answer was “trains,” but he thought (out loud) that it might be “motorcycles.” He used a 50/50*, which removed “motorcycles.” He chose trains and moved on. During the commercial, it was found that there is a magazine about motorcycles called “Iron Horse” so “motorcycles” was a fairly logical answer, so they gave him back the 50/50 lifeline. BTW, this was on a pretty low-value question, like $300 or so.
*I assume you know this but just in case: “50/50” means two (randomly chosen) of the three incorrect answers are removed, leaving only two answers to choose from. You can only do this once during the entire game.
Actually, that was an episode of Jeopardy!, not Millionaire. I saw it too.
And to Ravenman: contestants on Jeopardy! must wait for a commercial break to raise an objection. I’m a former Jeopardy! champion and still have the set of rules they gave us.