It's kind of a red flag that she is completely unwilling to talk to you. I think if I were you I would be working on finding out what that is about... to me everything goes along much more smoothly and with better results when everyone is talking and working towards finding ways to have a healthy relationship. To me, no contact is not healthy for a long term arrangement. Provided that is the goal here. If he just wants a short term thing, then maybe DADT (don't ask don't tell) would work for you... but then that is more of and "open" concept rather than a poly one.
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