sarah edmondson points to years of nxivm training. >> all the indoctrination, all the years of, "women are weak. women have no character. now is the time to prove i can do it." >> reporter: sarah gives another explanation for her obedience -- before she joined the secret sorority and got branded, she says lauren salzman had demanded highly compromising "collateral." >> you need to provide something to me that i'm gonna hold forever just to confirm, and to -- and to solidify that you'll never share the secret. >> reporter: so what did you give her? >> so i gave her a written confessional. >> reporter: she says salzman's demands for collateral grew more extreme. >> she told me to get the deed to my home notarized in her name. >> reporter: wait a minute, wait a minute. >> no, sorry. >> reporter: she told you to put the deed of your home in her name? >> yes. >> reporter: she didn't do that, but she says she did give in to lauren salzman's demands for a nude photo. authorities allege allison mack also demanded nude photos of her prospective slaves, which she then shared with keith raniere.

. >> reporter: former member sarah edmondson say women were forced to sign confidentiality agreementsol incorporating raniere's initials without any anesthesia. >> it was a horror movie. it was the most inhumane horrific way to treat anybody. >> reporter: abc news obtaining documents showing mack now in talks for plea negotiations. an indictment against both mack and raniere says they knowingly and intentionally conspired to recruit, entice, harbor, patronize and solicit persons. it goes on to say they engaged in such acts knowing that means of force, threats of force, and coercion would be used to cause such persons to engage in one or more commercial sex acts. in a letter posted last fall on nxivm's website, raniere said there is no merit to the els that we are abusing, coercing or harming individuals. these allegations are most disturbing to me as nonviolence is one of my most important values. he also said the sorority is not part of nxivm and i'm not associated with the group. actress catherine oxenberg, best known for her role in "dynasty," said her daughter told her she was bra