Based on what I see on the member website MS is clearly in the wrong. I would definitely pursue the matter.
b. Club Members with Ownership Interests at Multiple
DVC Resorts
1) In the event that a Club Member has Ownership Interests in more than one DVC Resort, Home Resort Vacation Points from multiple DVC Resorts may be combined as DVC Vacation Points for reservations made less than seven (7) months in advance.
2) If a Club Member requests a Home Resort reservation during the Home Resort Priority Period and the reservation requires more Home Resort Vacation Points than the Club Member has available in that particular Home Resort, he or she may borrow Home Resort Vacation Points from that particular Home Resort's next Use Year, subject to all Borrowing guidelines. Or, at the end of that particular DVC Resort's Home Priority Period, Club Members may use their Home Resort Vacation Points from other DVC Resorts as DVC Vacation Points to complete the reservation.
3) Club Members cannot apply Home Resort Vacation Points from one DVC Resort as DVC Vacation Points to any other DVC Resort during the destination DVC Resort's Home Priority Period
Where's Dean when you need him!