Down in the crypt you encounter a sign that says not to proceed unless you have the Watchmen's Instructions.

Where are these instructions actually located? Guide online will show you how to get past the maze, but I can't find anything on whether these instructions actually exist.

IIRC, that's the chamber where there's a statue in the centre; if it is, I think . . . it's been awhile. . . the Watchmen's instructions is the direction at which they're pointing. . . read as '. . . unless you follow the Watchmen's Instructions.'

I really didn't give it much heed, and proceeded anyway. . . I don't remember the Watchmen being a significant factor regarding that whole maze/puzzle area. I DO remember that was a very annoying/challenging area.

. . . Seems like that Watchmen sign might've been just a game-design element that was abandoned or overlooked.