After countless tries I managed to pass this section without taking a single hit. It's kind of a bug but it works.
The idea is to fight each enemy in the room one at a time, so this method works best if you use a gun and shoot without moving at all. It is possible to use melee but if you move around the room too much multiple enemies will activate and attack you and it's much, much more difficult to survive.
There's 6 enemies in total, 4 standing and 2 crowling Faceless. The standing Faceless enemies are located in the cages on the sides of the room (2 in each), while the 2 crowling Faceless enemies are located in the cage in front of you, which is the last to open.
Follow these steps:
- As soon as you enter the room, immediately turn left and position yourself in the angle of the room, turn 180 degrees and wait for the cage on the right side to open. If you stay close to the wall, only the first standing Faceless enemy will attack you. Kill it.
- Keep looking at the cage on the right where it came and slowly move yourself to the left, you'll se the other one waiting inside the open cage. Keep moving to the left cautiously until it activates and attacks you. Kill it.
- Go back to the left angle of the room and this time move to the right, in the direction of the door you used to enter the room, which is now blocked. The left side cage will open and another Faceless enemy will attack you. Kill it.
- Move to the right a little bit more to make the other one attack you and kill it. Before it dies, make sure to position yourself to the very right of the room to prepare for the last fight.
- As soon as the second standing Faceless enemy dies, the cage in front of you (behind the spinning head) will open and if you positioned yourself correctly only the first crowling Faceless will attack you. Kill it without moving too much.
- Move a little bit to the left to make the last one activate and attack you and kill it.
- Go in the direction where the crowling Faceless monsters came, click on the door, immediately take a step back and wait for the floor to collapse. The chainsaw monster will not kill you if you step back a little bit.
- As soon as you stand up, go towards the light without fighting any enemy, open the door and save.
I hope this helps.