None of the visions or common spawns in this zone have a set look. In fact, if u were to zone into DS and come straight back, the one at the door would look different. They dont see invis btw so i could test this theory unaffected. It spawned looking like a coterie vamp, then i zoned and back: a shissar, then zoned and back again: a phlarg fiend!
My friend was raiding Grieg's End yesterday and he was saying the vision type monsters appeared to be something different to everyone, it could be a wolf to one person, a troll to the other, and ogre to the next, then a high elf, half elf, wood elf, orc pawn, bixie, dragon *shrug*