Ela did NOT exchange her exam papers with Sanju's

It's much deeper than we may have imagined, and rogue sports supervisor Daljeet is likely to be the mastermind behind it all. He may have been tailing the BFFs when they took the wrong turn, likely to have brainwashed Varun when he went missing, then followed them all the way to the party site and then followed Ella and Vinnie to the point where Varun fell off. His "one down, three to go" line may have something to do with what really happened to Varun, and he's been trying really hard to split the BFFs apart.

Whoever exchanged the papers, if not Ella, is possibly working under Daljeet's orders.

I also have to add again- this is a stupid, laughable excuse for a law college. Can't they have seat numbers written or printed on the answer sheets?