that's not just the movie vampire. vampires traditionally, in folklore, are harmed or repelled by the sun, hence the appellation "Creatures of the Night."
but, even more importantly, if they were vampires, you'd think a necromancer's undead spells would work against them, but they don't.
Have you read Dracula? You will notice a scene where dracula is seen in the day light in human form. Only in later media has a vampire been burned in daylight. Old world myth has them uncomfortable and unwilling to enter daylight but not actually harmed by it.
Sorry, hit the enter key. But they guy are really vampire are they. I have never seen them actulay TRY to be like a vampire. I seen one chase someone out side and then stayed there in the sun, in vampire turms, OUCH I'm melting. It might be a little cooler if they were rouges, them they have the basic vampire frame.