Looking at TripAdvisor, the resort appears to be well-reviewed and in reportedly in decent shape. The negative comments are largely about timeshare sales weasels, which is pretty ordinary. So it doesn't seem like the resort was de-listed due to quality issues. I wonder if instead the resort stopped (correctly) verifying deposits, or there was some other management issue? So, it is possible that there aren't huge special assessments in your future.
Your first step is to figure out what you actually own. Is it a fixed week, or a floating week? If fixed, which one? If floating, which week(s) can you reserve and how do you do it? What unit size(s) can you book? Large units (at least 2BR but larger is better) in prime time (summer, and specifically the first full week of June through the third week of July) will be the most attractive.
Once you've figured that out, you have a few options.
One: you can use it yourself, even though it is a bit far. Vacations are vacations.
Two: You can try to rent it out and use the proceeds for your own vacations. Branson has a lot of supply, so this probably only works if you have a very high-demand unit size/time.
Three: you could investigate independent exchanges---these include 7across, HTSE, or TPI. Depending on exactly what and when you can book, SFX might even take it, but that's iffy.
Four: You can see if the resort will take a deed back in lieu of foreclosure, and if they won't just allow them to foreclose. To do this, you have to threaten (and be willing) to stop payment and potentially take a small hit to your credit. That might not be the worst thing in the world if you don't like your other options.
