Silent & Sneak is the most difficult approach. Enter from the waste disposal. I am playing on 2 PCs. Check the placement of the security guards. The placement of guards is different each time on this floor. Shoot in the security gate with a stun gun before entering. The guards wearing a suit don’t wear armor and can be defeated with a body shot. If you are just under the camera, it will not work. If you do not enter through this door, you will be taken by the camera. Guards have poor eyesight and cannot be found through bulletproof glass. A guard will come up from the stairs, so knock it down.
If this patrol guard is not defeated, a body will be discovered. The safe room is omitted. You will be found if you do not walk the end just here. I’m hiding because the guards are coming over. This route is relatively safe to escape. When the prepared car is far, use a stray car. This time I will use a helicopter. If you use this route, helicopter will respawn..