I am almost certain that Non-Volokh is neither Sasha nor Eugene Volokh, nor any other of the identified conspirators.
Definitely not Sasha -- as he is away on his clerkship, and I don't think he would continue to post under a pseudonym if he explicitly has said he doesn't believe it apporpriate to blog while clerking. (BTW, you said he was gone for two years --- I know he is at Kozinski's, but does he have a SC clerkship lined up?)
I think that Non-Volokh is Volokh. Read the link to him, which reads thus:
The Official Juan Non-Volokh FAQ:
Q: Hmm; Juan Non-Volokh. What kind of name is that?
A: A pseudonym.
Q: That sounds fishy -- what does he have to hide?
A: His name.
Q: Oh, pretty please, we're soooo curious -- tell us who he is.
Q: Ah, I've got it figured out: This is actually your own pseudonym, so you can post things that you'd be ashamed to see under your name.
A: I have no shame. More importantly, if it's good enough for Publius, Lewis Carroll, Mark Twain, Vladimir Lenin, and Josef Stalin -- wait a sec, strike those last two -- it's good enough for us.
Q: And his e-mail address?
A: jnov at hotmail.com.
Sounds like Professor Volokh to me.