There is a current fatal flaw in the game in the Pyramid. I have the same problem as Chance does; where I can't switch between characters after a certain point to have everyone be able to progress through the bridges section. I can't progress, nor can I even reset their positions because the A Key's function is removed.
Edit: In addition, the new Map RTX Data does not work.
Edit 2: Going back on a save file fixes the issue, but it broke again after the fight after the first bridge section.