Basically, task was whichever couple wins, they would get a chance to go to main house at the expense of 5 lakhs deducted from prize money. Jay ka logic hai ki he does not want 5 lakh to get deducted so he wants no one to win.
Kundra usko bola ki jo bhi show jeetega he will give 5 lakhs to that person from his own account. So Jay started playing with Kundra and against his own teammate Pratik.
What I think is its just bullshit. Jay despises Pratik and koi bhi fuddu logic deke he wanted to ruin his chances.