Abhay, it is for a reason that you felt uncomfortable around Alina.
1) She escaped that dark room. How?
2) She was stalking you and observing you and Piya.
3) Her mother found her in the woods and cemented her inside a room, so that she could not escape again.
Now, there is more,
4) She cried for help and instructed Danish where to find her. She told him about the painting, about pushing the bricks and getting her out.
BUT when Danish asked her how she got into that sealed room, she said she had no idea, she was just wandering and got stuck.
Now, Danish too was so obsessed with finding evidence against the Khurana's that it did not occur to him, that if she had no idea of how she got trapped, How on Earth did She Know that She was trapped behind that Big Painting?
Abhay, you too are making the same mistake as Danish. You are busy collecting evidence to expose and put the Khuranas in a spot, forgetting what you sensed the first time.
You were really uncomfortable about Alina. Trust your instincts. There is more to her than meets the eye.
And what is in that red coffin? Maithili? Maithili held prisoner by the Werewolves?