I have a Marriott Newport Coast which I bought externally (in 2009 not from Marriott), and recently (Dec. 2013) enrolled it in the Destinations Program. However, because I bought externally, I cannot trade it for Marriott Reward Points. The VCP I would receive is 3475 if elected for VCP. Marriott's materials indicate only certain ownerships, generally if purchased from Marriott, were able to trade for MRP. This is the benefit I didn't get buying externally.
However, you enrolled your week. By enrolling your resale week, it opened up the ability to exchange it for Marriott Reward Points.