I didn't get questioned because they don't care and I never ask a permission to go to the toilet, restaurant or event. From now on, I will always ignore security guards standing on the hotel's entrance because they won't asking me, and I will never asks a permission unless I'm getting questioned. This also proves to be 99% successful on previous hotels I've visited before this "disappointed day" (also for the 7 different hotels). Maybe in that day, I was actually wrong because I was ask a permission to use the toilet and caused me to failed finding the elevators.
Maybe someday when I happened to be in Oberoi Street, I will tried to enter that [undisclosed hotel] to film the elevators, and hopefully I will not get familirized by the same guard who was escorting me to the toilet before (well I will just gonna ignore him no matter what).
Maybe try walking in when a car is entering a hotel if you were questioned at the entrance gate*, so that the guard will be focusing on that car instead of you. If you were questioned at the entrance door**, try waiting until a driver stops at the drop-off area, and follow people who get off the car.
*Entrance gate: Where cars enter and people walk in to the hotel area.
**Entrance door: Where people walk in to the hotel building.