I'm surprised the Dunmer still believe in the Tribunal, since the Nerevarine took Vivec's powers away over 200 years ago.
I'd have expected them to go back to Daedra worship. Especially Azura.
There will always be some who cling to the old ways, after so many years it's pretty easy to come up with a personal view on the happenings. Who's to say that the supposed nerevarine wasn't just a person who together with ashlanders and other supporters conspired against the tribunal? Vivec proves his power in the trials and dissappears, maybe it was his last statement of godhood before he ascended into the heavens where he rules?
Far fetched ideas spawned from no evidence or personal recollection but when you're a fanatic it dosen't really matter. I would seriously doubt that a lot of the dunmer still follow the tribunal. However I think that when a lot of time has passed and most people from that time are dead a small revival isn't illogical.
Also on a side note, morrowind did go to hell when vivec dissappeard, the argonians did attack morrowind when they had the chance... What does this tell? That the dunmer went soft and failed,
therefore the whole "we can't be misslead or show remorse this time" will be a popular view among some nationalists I can imagine.
It would be nice to see some sort of house or new organisation that strives to bring back the old "glorious" days of the tribunal.