It was Sidhu who asked contestants to stage a walk-out (remember Gajendra singh said it was one of the judges who was behind this).
1) He was upset that Ismail insulted him by walking out when he was the judge.
2) He remembered that he had used his walk out to a good effect when India toured England.
Seriously, it's Gajendra's responsibility to let us know what happend. If not today, but after the finals.