Okay, so I just did more observation and testing, and it seems that the sensitivity of the doors are inconsistent between directions: the initial position given relative to a room can trigger top, left and right door to open, but not the bottom; the hero needs to move closer to trigger it.
...Wait, what? But this is what the hints page is saying:
isPathClear function to find which doors are open as you navigate the maze.
So you're saying isPathClear can see through closed doors when the hints are implying otherwise? I... don't know about anything anymore.
And yes, I still stand by my point; it has nothing to do with any code being wrong, but about the level behaviour being unintuitive and not what is being stated. Even if I follow the standard algorithm perfectly I won't be able to solve the level because of these problems.