Went through Caer Lem the first time, then went through it to the end a second time and fought some deep spiders before finding and using the sub-quest board. Unfortunately, this second trip has left the bridge facing the opposite side, and no amount of fly, spiderclimb. or jump will allow me to get across and turn the bridge around for the rest of the party (when I went back a third time after discovering the sub quest board).
Quite literally, I can cast misty step with fly active and be one square away from my target, only to immediately fall to my death. This is honestly why you prep the entire environment and don't cut corners with rendering the entire dungeon.