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The Mage's Guild member (Wizard Nisira) posted outside the warded door mentions needing to talk to the Artificer to get permission to enter. When I talk to Telenger, though, there is no dialogue option relevant to it.
I think I entered in beta during one of the last Auridon quests (but I might be remembering wrongly). Did not find that option during my "real" post-launch run so it might have been disabled along with the Skywatch frog race quest and the loan shark quest in Vukhel Guard.