A mistrial equals a re-trial!! That is certainly no acquittal.
I took a brief look-see, and I think you're right.
I don't think Geragos is going to even move for a mistrial. I think he'll just play the "horror" of Brocchini's supposed "perjury" for all it's worth, till the judge tells him to sit down and shut up.
Whatever Brocchini or Distaso forgot (or, in Geragos' world, misrepresented), there is plenty of time for the judge to take remedial measures.
If Geragos sincerely asks for a mistrial, it would be b/c he didn't think he was winning the case. If he asked for one, he might get one (though probably not.) If he got one, Scott would get to sit in jail for another year until the state retried him. I don't think he'd have Geragos second time around. Not enough money, probably.
As RG said, that's it. Let the trial continue.