What she said.

Because it's such a sensitive situation, I'd treat it like Ritual. It has no place on the internet. The only qualified answer we can give you is to consult your advisors. That's what they're there for. In all serious matters concerning your organization, talk to your Chapter Advisor. If you feel that you're not comfortable in doing so, is there a Regional Director or HQ officer you can contact? You say you're in a very well known sorority, so I'll assume that yes, you have higher ups you can talk with.

Please don't disclose any information on the message boards, including the PMs. This sounds like something that should be handled internally.