We're a community, even if we're under the thrall of all this sparkling vampire drama we can still do things for ourselves while Zenimax sorts out the whole debacle.
If you don't like vampires, or at least those blatantly abusing unintentional effects in Cyrodiil, simply refuse to group with them. If you're grouping with them so they can carry you to victory, you're worse than they are- because while the vampires are relying heavily on a crutch to be "good" at pvp you're relying on the crutch of someone else, but I digress- Simply don't group with anyone who is a vampire in Cyrodiil.
Expel them from your raids. Refuse to trade with them or buy their wares, especially if you notice that they are selling things through guild stores. Tell them how much you loathe them when they ask for a group. Mail them piles of garlic in the mail.
As a community, we aren't totally without capability, and we can let these people, who are ruining the fun of everyone else for the sake of their own egos, understand how terrible they are. Our fun is at stake, and we need to take the those stakes and plunge them into the greedy hearts of these players.