/Mangum will break from the pressure and confess that she's lying.
If the AV breaks from the pressure, she is likely to say that she has told the truth, but has decided not to proceed because of the stress.
If that happens, and I agree it's a strong possibility, I certainly hope the defense will pursue whatever avenues are available to get a factual finding of innocence, as well as a pursuing a civil suit against her in order to get her inconsistencies on the record.
Don't be surprised if Nifong tries to finagle a way to keep her from testifying, such as lack of mental capacity, fear for her life, etc., and still pursue the case, or get the court to agree to allow her to testify from behind a screen by video, something like that - anything to allow her to lie without people getting to see her face and reactions to questions, and to get sympathy from the jury.
Don't be surprised.