From Ruined Era Welryn, my level 20 FG exited south towards Welryn docks. When the loading screen cleared, I was in the Sanctum of the Architect getting spawncamped by a lightning elemental. Exciting times!
When I managed to break out of the loop, I returned to Welryn and took the same door; ended up in Welryn Docks correctly. I’m guessing this was a glitch in the multiplayer world server logic.