Insomnia project - where is the broken air vent?

I know it's a long shot finding an answer here since this is about the initial demo of a Kickstarter funded post apocalyptic RPG called Insomnia Project that's still under development. The game's own forums are mostly in Russian and I couldn't find an answer there. (The game itself is beautiful and uses the Unreal 4 engine, check out the demo here)

After handing over the package in the generator room, I'm told to get out via a broken air vent and avoid the soldiers who have appeared nearby, blocking the way back. I can't find any such vent nearby, does anyone know where it is?