Forgive me, I'm still pretty new to Dev Tools and I don't know how to see the names of rooms or pipes. The only map I could find is the 1.5 version of this region from the Russian wiki, but I was able to edit it to show the issue.

https://i.imgur.com/CXFZNT1.png

Above is the region map as it appears originally on the wiki, and the 1.9 in-game map seems to align with these routes. A <-> B, C <-> D, E <-> F

https://i.imgur.com/o1Xeyen.png

The image above is what I'm encountering in-game. A <-> D, C <-> F, E does not appear to exist, and B is a dead end that ends with me getting stuck and having to exit the run. I've only tried this with Rivulet and Saint, but the same issue exists for both of them.