I really doubt it. MS pays for trades out of the system by renting your DVC points. I can't think of any incentive/reason MS would have to book a non-DVC resort for anything but points.
I think Keystone is a great resort, but you'll have to book it someplace besides MS if you want to pay cash.
To my knowledge, MS will not do cash reservations for the CC, etc. The only exceptions I can think of are the cruises where one is paying for the first adult with cash.