I think that if Namie is a "diva" it's probably because people misinterpret her personality.
I wouldn't think she's overly shy - at least not to the point that it would interfere with her interactions with other people - rather I think that she's probably just not a readily open person. Meaning that whenever she meets someone new she probably doesn't act super-duper friendly because she'd rather get a sense of who they are first. And if she feels comfortable with them and, for lack of a better word, "accepts" them, then she'll open up.
It also wouldn't surprise me too if maybe she just feels more comfortable interacting with employees and associates (dancers, stylists, etc.) in a formal business manner ("We're here to do a job. So let's do it!").
At least that's what I think since I've often been told that I can put people off or make them feel uncomfortable because I'm not very talkative or animated when I first meet them. I'm more of a listener.
