Mike!
Official Ponylandistanian National Treasure. Re
Why was she called to testify in the first place? How was her testimony probative? Was this theater on the part of the prosecutor?
My guess would be, they wanted/needed to take the public testimony people had made (News, Oprah, etc.) and show them for the fallacies they were, directly before the grand jury. Otherwise, after the fact, there'd be an outcry of relevant 'witnesses' not being allowed to testify before the GJ. And we can't have that, now can we?