Mack was allegedly a member of a group within the NXIVM organization called DOS.
It is unknown at this time whether Mack had agreed to a cooperation agreement in exchange for her plea.
As part of the secret group inside NXIVM, known as DOS, women were pressured to have sex with Raniere and brand his initials into their flesh, court papers say.
The original indictment claimed Mack “recruited women to join what was purported to be a female mentorship group that was, in fact, created and led by Keith Raniere.