Agent Bond was sent in his place. I think it depends on how the subpoena was issued.
She did what she could with the information she had, but was unsatisfactory.
And why wasnt Cheney for that matter or why didnt Libby testify after falsely telling the judge and the jury that he would. The judge only allowed certain evidence in because Libby's lawyer said Libby was going to testify. He was visably pissed when Libby did not testify after making the assertion that he would. The jury was also disappointed because Libbys DEM lawyer implied he would testify in the opening statement.