I know it is a popular thing to write the Oregon Vortex off as fake.
I think that is beside the point. When you go see a magic show, you know that is illusion. If it's done well, you are still entertained. That may be a more sensible viewpoint.
As it happens, at Knott's Berry Farm they had brought back a part of the Haunted Shack for the anniversary. What you have is a photo op in a room that has a slant, but it doesn't seem to be a big slant. I appear much taller than my sister; I am shorter.
It also occurs naturally in a cave in Farmington, Pennsylvania.
The other thing that makes me suspicious of the House of Mystery is that for a building constructed in 1906 and sent downhill by a landslide, it feels pretty solid.
However, you do see a level and a plum line showing you that things should be one way, that is not the way they look.
Outside the shack you see water flowing up and golf balls rolling up.
At least, that is what it looks like you are seeing.
An investigation show, Fact or Faked: Paranormal Files, visited. They did agree that some of the things that you were seeing only appeared to be happening that way, and it was optical illusion. However, there were other things that they couldn't explain.
One is that in addition to the optical illusion, visually impaired people and people closing their eyes or blindfolded still hear and feel a change. In addition, the perceived difference is bigger than the actual slant should allow, and warm-blooded animals really do seem to avoid the place.
I know that when my sister was changing places with another person, I "saw" her body shrink. No, I don't think she really shrunk, but that is how it looked. I can't explain that.
That particular mystery happened outside of the house.
https://www.oregonlive.com/movies/2012/06/fact_or_faked_paranormal_files.html