When police is investigating the murder of Mrs. Sethi, they doesn't bother to even ask to get the CCTV footage been checked. These dates the lobbies too have them installed.
Vikram informs that the book launch party was as Hyatt, where as when Vikram come to hotel to check on his wife, it was J W Marriott. Wonder, if the Marriott didn't had space for Mr. Sethi's book launch.
Vikram, was driving a Mercedes when he hits the divider and rolls over. Being a Mercedes , upon impact the air bags should have inflated and Vikram wouldn't have been so injured. Also, the windshield was intact.