Dhrishti, that seemed like Maya's hand to me. Notice that whoever it was, they used their left hand. When does a right handed person use their left hand? Yes, when your right hand cannot be used. There's a bandage on Maya's right hand, would have been a give away had they showed her using her right. Plus, the scene right after it and her dialogues. Hands were thin, long and slender, without nail polish. It looks more like a wrist band of sorts (possibly to cover the chuda) than a long sleeve blouse to me. I'm totally going to throw the timeline factor out of the window here because timelines are screwed up in this show and according to Maya herself, she's everywhere. So, Maya's my best guess.
Although, I'm game for Jhanvi as a possibility too. That would mean both Maya and Jhanvi are in this together and Jhanvi's been faking coma on Maya's orders. That hand though, it looks too young to be Jhanvi's hand. No sight of any wrinkles or skin showing signs of older age woman. Jhanvi has zero motive of her own to go after Vikram.
Shipra is a far fetched theory, imo because Maya wouldn't ever associate with Ashwin's live-in partner. No motive of her own as well.