The television star, 35, has agreed to live with her parents under house arrest after pleading not guilty to playing a major role in recruiting women for an alleged sex cult run by self-help guru Keith Raniere.
Federal prosecutors in New York charged Mack with sex trafficking and conspiracy for recruiting women into a programme within Raniere’s organisation called Nxivm, representing it as a female mentorship group.
She is accused of forcing the women to have sex with Raniere and to take compromising photos of themselves.
Mack was arrested by the FBI after being accused by two women of directing them to engage in sexual activity with Raniere, 57, who allegedly gave Mack money and other benefits in return.
Authorities have said she acted as Raniere’s own “slave”.
Prosecutors and Mack’s lawyers said in a court filing that the two sides are engaged in plea negotiations.
Raniere was arrested on sex trafficking charges last month, and is being held without bail.
Authorities have accused Raniere of running a secret society within Nxivm (pronounced “Nexium”) where women were branded with his initials, put on extremely restrictive diets and forced to have sex with him.
Upon joining members, who numbered as many as 50, were required to provide information about family and friends, nude photographs and rights to their assets, which were used to blackmail them into staying, according to prosecutors.
The women were taught that the society would empower and strengthen them, prosecutors said.
Nxivm on its website calls itself “a community guided by humanitarian principles that seek to empower people and answer important questions about what it means to be human”.
Raniere said he was “deeply saddened” and denied “abusing, coercing or harming” anyone in a letter posted on the site.
US Magistrate Judge Viktor Pohorelsky set terms that prohibit Mack from having any contact with Raniere, Nxivm or anyone associated with the organisation.