I'm new here, actually joined specifically to share my theory:
Spoiler Vivec. True, he lost his godhood after the Nerevarine took down Dagoth Ur. And he disappeared during the Oblivion Crisis (some say he was pulled into Oblivion, some say he fled to Solstheim, but nobody knows for sure), and he is most likely dead. However, it's not so easy to kill a god, even one who isn't a god anymore. I believe he may have found a way to stay alive for the past two hundred years, to face seeing first his city then his entire island destroyed (the Ministry of Truth fell on Vivec City, and then Red Mountain erupted). One way for him to stay alive may be that Azura further cursed him to see how far the Dunmer have fallen.
Vivec achieved CHIM, so by all means, the loss of the Heart of the World does not mean as much to him as it meant to Almalexia and Sotha Sil.
You may be interested in this:
http://www.imperial-library.info/content/trial-vivec
It's not offical lore, but written by a former Bethesda writer, Michael Kirkbride (and some other developers). MK is the guy behind pretty much everything story- and lore-related in Morrowind.
Also: where is it mentioned that Vivec fled to Solstheim?
I can only recall that he could have been taken by the Daedra.
Welcome to the forums.
