Kish and Suyash got constantly bashed every weekend and they were also being called as bullies. Suyash got eliminated and they are hoping to marry soon. This show is about money and they desperately need it. The amount is huge.
Point 2
Kish got caught into a tight situation with dear brother Prince. What better opportunity to redeem herself from the bully tag. The show will end soon but the impression may remain so this is the best opportunity to wipe it off and leave with a lump sum.
Point 3
She saw that prince wasn't budging. So instead of forcing him to leave and herself going into last week was good but what if she didn't win? Bad image still remains and no money at that cost. That was of no use.
Point 4
Most importantly salman will be impressed. Like it has happened now. She was constantly told off for spitting in the drink and now look at Salman praising her! She's hit many birds with one stone. Maintained relations with brother, improved own image in front of audience and Salman plus got the money.
Clever move by the master manipulator!