I think it's for money. She has her belief system and when this phone call came in she probably thought she won the lottery.
I don't doubt for a minute that the DT had watched her on YouTube and heard through the grapevine what her views are. Nurmi may have known her through the court system.
Hasn't it been reported that the defense approached 6 0r 7 DV experts and they declined? Seems to me they were desperate.