Since you already have a reservation, I'm not clear on what you want the member to do, or why. Is it that you think it would be cheaper to rent from a member, so you want to somehow replace your cash reservation with a points reservation?
To expand a bit, as a non-member, you can't do anything with points, since you can't make reservations with
DVC. Members can transfer points to another member, to add to their own points to make a reservation, but you don't have a DVC membership to transfer points into. All that a member can do for you is make a reservation for you with their points.
Now, it's possible that a member could make a reservation at SSR for you, and you could then cancel your cash reservation. The problem is, you're traveling at THE most popular time of year for DVC reservations. Many members made their reservations for that week in December way back in January, so trying to reserve in October is hopelessly short notice. If you'd be interested in renting from a member in the future, you really need to start the process much earlier. Members can book their home resorts at 11 months out and other resorts at 7 months out, and if you're traveling at a busy time like December, you should be looking for a member to work with about a year ahead of time.
Hope that made things a bit clearer....enjoy your stay at SSR! It's a beautiful resort.