I absolutely hate B8, the thing is a mess.
It does note in B1-9 - In Search of Adventure, that that module was originally a one-round tournament (maybe at Gencon?) where apparently parties could select one of the three paths to take. Not that there's any hints or foreshadowing what sort of challenges is along the three paths, you just have to blindly pick and hope you choose one your party can handle. Overall, it's still pretty non-nonsensical (puzzles that don't have a logical means of correctly figuring them out or encounters where the party is WAY out of their league where only blind luck will prevent a TPK), EXTREMELY railroady and all-in-all, not much fun to run. I tried running it back in the 90's for a group, and we just gave up on it because it wasn't any fun at all.