Curious question about Movarth. Since he was infected by a Cyrodilic Vampire, if he were to infect the player, wouldn't we actually catch the strand of vampirism associated with Cyrodil?
Yeah, this is one of those things where there definitely needs to be a reasonable explanation, preferably one that doesn't go something like, "Oh, it was just an oversight, that's all!"

They might explain it, or they might not, but seeing as this created much confusion, then it probably should be explained better for the sake of the fanbase.
Thats the problem that spawned many threads and contreversies on the subject. Higher vampire NPC's are called "Volkihar", but Movarth was bitten by a Cyrodiilic vampire. And Cyrodiilic vampires are the only vampires that can blend in society through feeding. It is possibly they ventured to Skyrim and took over as they did in Cyrodiil, but the "Volkihar" title on their foreheads is extremely concerning.
Maybe it's a case of mistaken identity? It could also be possible that the "Volkihar" in vanilla are actually Cyrodiilic vampires, and they just adopted the Volkihar name in order to make themselves sound more threatening than they really are? I'm guessing they'll explain this mess somehow.