I wonder if it would really just come down to a simple multiple choice of luck.
If they've gone out of the way to prepare a fake two-way magic circle, then wouldn't it be fine for there to be just one other as the real thing I wonder?
As the answer to a puzzle, isn't having three of them just pointless, I wonder.
No, it's not as if it's an escape game; there's no obligation for the labyrinth to have prepared a hint, I guess.