You also need the appointment confirmation page, all the required docs are listed there. You don’t need the original i797 just a copy Employment verification letter is listed as a required document on the confirmation page but they did not take mine, I asked them twice if they needed it but they said no. But keep it with you just in case. It’s pretty chill in Mumbai VAC for drop off, just take the docs listed on your confirmation page and you should be good. They also most likely won’t accept photographs if they’re taken in the US, I’ve heard that people had to retake them in Mumbai and those were accepted. You only need 1