Once you reach the workshop to the west of the holding cells, you will notice a hatch that cannot be opened. Grace comments that it is impossible to lift it without proper tools, but there is no need to hunt for any special equipment — if you follow the intended route, this obstacle will disappear on its own.
Story progression steps:
- Leave the workshop and remove the previously inserted Joint Plug — this works just like with the empty injectors.
- Insert it into the socket next to the door that leads to the furnace room.
- Move forward into the area with the forklift, where a zombie is roaming around.
- Kill it using your weapons or a Hemolytic Injector.
- After that, pick up the second Joint Plug lying next to the forklift.

As soon as you take this key item, the lights will go out. The only available path will be the open ventilation shaft on the right side of the room.
Important details while crawling through the vent:
- Inside the narrow tunnel, on the left, you can find a lockpick that will come in handy later.
- When you turn right, a scripted scene will trigger with a monster being dragged away by the Girl.
- After exiting the vent, you will find yourself back in the same workshop, and the hatch that used to be welded shut in Resident Evil Requiem will now be blown open.

This means there is no need to search for any tools. In the place where the zombie vanished into the vent, you will find a pool of «Infected Blood». Make sure to collect this resource — it is crucial for crafting powerful items and will make surviving in the sewers much easier.