Reading the book A WARNING, it seems to be someone with a background possibly in history and international relations and someone who works in one of the agencies, like DHS. Anonymous might already be out in the public eye, just not saying he/she is Anonymous. This sounds bad, but I don't think Conway is smart enough to write a book like "A WARNING." (I'll apologize if she turns out to be Anonymous)

Miles Taylor is a possibility. Like Anonymous, he claims to speak for a small group of "Others" who will come forward.

It's possible Anonymous has come forward, but just hasn't announced that he/she is Anonymous.

Someone else came forward this week too from DHS, a woman whose name I can't recall.

Some people think it's Kirstjen Nielsen. I was leaning towards Dan Coats, but now I'm having doubts.

EDIT: It's not necessarily "White House staff"; it's an official in the administration.