Two reasons...
Upen engaged Gotham and challenged him that he will hit him and will hurt Gotham's face and Gotham not only backed away but cried and complained to the captain Dimpy... This whole incident proved that Gotham is weak... while Upen looked fearless and clearly won the first round of confrontation..
Secondly Gotham knowingly that he will be saved even if he losses the Hijack task still continued to fight Karishma for 36 hours because of his ego... what a waste.
Gotham tucked himself into that chair for 36 hours is like he was absent from the show along with Karishma... trying to stay away from Upen's wrath...
This gave most of those 36 hours to Upen to hog majority of footage and limelight which actually saved him ... now Upen know the exact formula for winning and may go all the way to win the season.
With Parneet's eviction one thing is now confirmed that public votes don't count... Colors have no respect for the money people are spending to save their favorite, one sving grace for voters though that most of the votes using texting are free..