I am also renting points for this coming December. I got my confirmation letter already from the DVC member. I wanted to call the resort ( BWV ) to confirm the ressie. I explained that I am renting points from a member and they told me that they can't check on it from the resort. They eventually directed me to the member services number, where I explained that I am renting the points from another member.
They were able to confirm my reservation, and also take down any of my request.
SIDE NOTE: Although my questions were answered OK, the guy on the phone seemed to be in a nasty mood.