Well, the plot thickens and Ivanchuk has now stated that:
"This all seems like pure madness!! But such spectacles sometimes happen in our world. I simply left, being upset after losing a game, and did not listen to a man who I was seeing for the first time in my life, and whose identity I don't know until now. You see what a comedy it was"
So his position is that he wasn't refusing to test he simply ignored a stranger. I can't independently verify the truth or falsity of this statement but it seems plausible (of course my opinion has not changed ... it doesn't matter if he was as high as a kite).
As a side note Arthur Kogan has been circulating a facebook petition that if FIDE bans Ivanchuk we will ban FIDE. Personally, I'd like to do that either way so I joined the group immediately. Yay for Arthur Kogan!