If an Illusion chamber on the path to the exit disappears, how do you rebuild the route?

Question

Accepted Answer

Build a new path by placing a tile adjacent to the one you stand on, which can reach the Chalice or the exit. A secret passage treasure can clear the way, and it helps to keep a spare spot open so you are not sealed off.

Escape: The Curse of the Temple

If an Illusion chamber on the path to the exit disappears, how do you rebuild the route?