There are enough weird circumstances involved that it makes me think it had to be put in intentionally.

• why is there a gap in the collision there? The terrain is basically flat, the wall is basically flat, it doesn't make sense that there would be any misaligned triangles
• It appears that, when you fall, you don't just fall into the floor. You fall down and then get teleported upwards. But not straight upwards, your horizontal position gets offset a bunch as well. This puts you above the stage at a not-quite-perfect position to get into that weird hallway
• The weird hallway. There appears to be no way to access it apart from falling into it from out of bounds. It connects to the maze, which is accessible from other areas, but why wouldn't that hallway just be part of the maze map? Why would it be here?

I'm not sure how to actually go about proving whether it was intentional or not, but these details irk me.