First of all shukla and vishal should not be a part of the captaincy task once all have decided that they should be out of captaincy race.
Secondly BB knew shukla group is less in number so he gave shukla the right to play from paras's side and made paras sanchalak . As this is kheecha taani game and we all know paras can't do because of his wig, Whereas shukla can use his aggressive force and get away with it.
Thirdly Paras was made the sanchalak and he played his game. They knew they are less in group so will not be able to play fairly and they stand no chance . So he cheated a lot in the task. And when in protest the other group retaliated the task was cancelled.