If Sylar is going to go, that will break Elle out of her general apathy and she'll head over there. She might have the intention to spectate at first, but obviously, that wouldn't work out. ;)

She will have NO problem killing people and may quite enjoy it, but she'd feel bad at seeing Sylar upset. She...uh, might try to kill more people so he doesn't have to get to so many? :P She's helping!