[SixOfSpades]

I've never tried Valen, but here are a couple of things to try, before resorting to the CLUA Console (having 2 copies of a recruitable NPC is just asking for trouble):
1) Being a Vampire, she's not all that likely to be outside during the day. What time was it when you searched the Graveyard District?
2) Even if she's Invisible, you can still probably check for her presence with a Detect Evil or two.