It's highly unlikley that you'll be able to exchange into anything in Key West in January at this late date, even with a great "trader". There are only a half dozen or so timeshare facilities there in the first place and your date window is only 16 weeks away at this point...
I don't like the place, but you
might find a Saturday to Saturday rental at Coconut Mallory in Key West. Check RedWeek, MyResortNetwork, VacationTimeshare Rentals, etc. for rental listings. In my experience, many owners at CM rent out their reserved weeks pretty routinely (all CM weeks owned are "floating" weeks --- there are no "fixed" week ownerships). Don't know if the "house" conducts rentals for owners there, but if so it will obviously be much more expensive to rent from the resort. Good luck.
P.S. I see a "float" 2BR week advertised for rent at Coconut Mallory on MyResortNetwork.com, with a reservation date range that includes your particular week of interest. Price is $1100 (no, it's not my ad and no, I don't know the advertiser and no, I have
nothing at all to do with that MRN ad). I'm not advertising, but merely making you aware of having seen something posted for Key West potentially fitting your specified dates of interest. You might even be able to negotiate a partial week rental --- I don't know...