I know this is an issue that other players have run into because I see the threads. I see the threads being closed with a note indicating that there are other threads, but I don't see the resolution.
I have several characters that are stuck in dungeon finder queue and have been in this state for more than three days. Another player who I play ESO with on a daily basis is also experiencing this issue. That player raised a support ticket, and received an unhelpful, boilerplate response that did nothing to help.
I've tried playing on different computers, different networks, forming groups, joining groups, leaving those groups, disbanding those groups, and nothing has helped. After joining a large group and staying in the group for a while and then leaving it, it appears that the problem is corrected, but it isn't. After logging off, when I log back in the dungeon finder will say "queued", "leave queue" does nothing.
Please don't respond to this by saying that there are "other threads" without linking to those other threads.