https://www.facebook.com/video.php?v=1538226653094042&l=8126293825157233825

Here's another vault glitch. You vault to the wall to keep player hitbox from expanding. Then you just have to be extra careful to not go too far from the wall and make your way to the second radiator. When you get past it just look at the wall, jump up without pressing forward to make the map unload and jump left and forward to get to the staircase. You can also reach it without jumping, but since you can't see anything you need to experiment with it and find a way that works for you.

This skip saves 6s compared to old window clip strat and maybe 2-3s compared to the door jump to the staircase.

im having problems with the vault glitch. is there something i have to pay attention at ? running and vaulting ? what do i need to do to keep the hitbox small i cant get it :/

You have to land close to the wall, so the angle you jump has to be right. You can test if you have the shrunk hitbox by pressing crouch. If you don't crouch, you have to glitch. That disables your jump though, so you can't do that on this skip, but it's good for practising.