I'm OP of this thread
Interesting video. Yes, I went there as Sabitsuki, I didn't even have all the effects.
If I remember right, the were several new blue areas in the Industrial Maze. I think I went there from the white area, where you find Monoko's effect. I activated the mark that allows you to wander freely on the white void, out of the hallways, and ended up in the white place in my first picture.
As you can see in the second part of my first pic, it leads to a blue area that is different than the one shown in the video. This is the left-most part of the maze.
The way to the Dead Hole is in the right-most part, another blue area.
Also, as far as I've noticed, there's only one difference between Sabi and Rust's versions of the area:
Oreko's ghost only appears if you are Rust.
So I guess it means Oreko is no more, after you turn into Rust.
I think she either died, or she turned into the homeless girl outside the Dead Hole (Charlotte was her name?), and she threw her iconical suit into the trashyard.