From what I understand, the channel and production houses always bring in some twist that participants don't know about. Prime example in Nach Baliye 2 when the jodis found out in Round 2 that they chose which couple gets eliminated. So I do believe Hiten when he said that they found out after the show started that they have to perform again.
Regarding Gauri's attitude, its been done and talked to death about. It depends on the viewer's perception, that's all. If you ask me, she was just composed and that's why she comes across arrogant to those who don't know her. Whether its award shows or any other, she is always composed on camera.
But she is the way she is. There are no excuses nor defenses for it. I like her because she is honest about herself and doesn't put up any pretenses of being fake. For me a celebrity being themselves is more important than coming across as a fake. Some people don't feel that way, obviously.
I think composure on television is more important than crying on television.
As for this being a scripted show, I don't believe it because Hiten-Gauri don't exactly need the drama/fame. Nor would Gauri put herself through this drama just for the sake of money. If that was the case, then she would have taken up a lead show with another production house for the money, since being a lead pays more and fame is more as well.
As for 3 weeks..., the only thing I can figure from that is Hiten-Gauri knew they would go out early because there is no public voting. Because there is no public voting and they are average dancers, they knew they wouldn't be able to stay on that long.
I also think that they were relieved because it takes up a lot of energy and time where they could use it in shooting or personal time for themselves.