Say there are no 1 br villas available for 1st week of Dec at a DVC resorts but there are 1 br villas available thru Disney central res for anyone to book (cash). As that week approaches, villas ever moved from Disney inventory to DVC inventory?
When a member uses points outside of the DVC system (except RCI exchanges), those points are converted to a cash villa thru CRO. These rooms can't be pulled back because they are already technically reserved using points.
When a villa is unreserved at 60 days prior to arrival, it can be turned over to CRO. This villa could be pulled back subject to CRO approval.
DVD (Disney Vacation Development) retains ownership of a small portion of each resort. These points can be converted to cash villas thru CRO at DVD's discretion. Not sure if these can be pulled over for points use or not.
Like Michael said, there are situations where DVC may have greater...rights to the rooms (for lack of a better term). But as a practice, they typically do not go into that inventory to reclaim rooms.
It would be very difficult to do in an equitable manner. Whatever specific room you may be looking at...it's very likely that dozens of members would have booked the room if it were previously in the inventory. And there could be folks sitting on a wait list for the same villa and dates.
If villas have been turned over to DRC to sell because a member used the equivalent number of points to book a non-DVC Disney trip, they have already been "booked on points" and cannot be booked on points a second time. DVC has to have the money that stay represents to pay for the member's out of DVC trip.