On Monday, disgraced Theranos CEO Elizabeth Holmes will play one of her last cards to avoid a prison sentence when a federal judge questions a key prosecution witness who expressed post-trial regrets about testimony that helped convince a jury to convict her for investor fraud.

That witness, former Theranos lab director Adam Rosendorff, made an uninvited visit to Holmes' Silicon Valley home in August. While he didn't speak to Holmes directly, Rosendorff told her partner William Evans that "he tried to answer the questions honestly but that the prosecutors tried to make everyone look bad" and felt "he had done something wrong," according to court documents.

Prosecutors have scoffed at the notion that Rosendorff's attempt to see Holmes casts any doubts on his testimony.

U.S. District Judge Edward said during a Zoom hearing Friday that he intends to ask Rosendorff a few questions about why he visited Holmes' home and whether the visit was driven by any doubts about the testimony he gave under oath during six days of the trial last year.

Davila emphasized that he expected the hearing to be brief and limited in scope after quashing a subpoena from Holmes' lawyers seeking any non-privileged communications about his testimony. "This is not going to be a fishing expedition," Davila said Friday,

Holmes, 38, is facing up to 20 years in prison for misleading investors about the progress her once-heralded startup Theranos was making with new blood-testing methods. She was supposed to be sentenced Monday, but the judge postponed that hearing once the Rosendorff questions arose. The judge set a new sentencing date for Holmes on Nov. 18.