Karen Lancaume and Raffela Andersson did well in Baise Moi, Rocco had a part in a controversial Mainstream Foreign film, and most actresses that star in Salieri or Dorcel film can handle dialogue better than Grey has. Rocco can switch from Gonzo to dialogue driven material with ease.

Mouthing Brandon's toe jam to Entourage is a feat, and Grey has crossover buzz to have a story arc with her in it (Jesse Jane was also in an episode before Grey), so it isn't much of stretch to cast her as one of Vince's GF's.

Grenier isn't much of an actor either. So it all evens out.