Fitzgerald is playing "Calvinball" (the rules keep changing as the game goes on). As far as he's concerned, nothing about the actual leak still matters...the only thing that matters now is Libby and Russert differed in what they said, therefore Libby was lying. All he needs to do is to assemble a jury of 12 Bush-hating Democrats and get them to find Libby guilty. Truth and justice are irrelevant.
No, he needs a judge that will allow him to keep all the evidence that destroys his case out of the courtroom.
I don't think he'll be able to do it. I think Libby's lawyers are going to eat him for lunch, and the case will dissolve before it ever gets to trial. It's all smoke.