I am ugrad at UW and a Wisconsin resident, so I am not 100% sure on how this all works.
You may consider attempting to gain Wisconsin residency if you are concerned about OS tuition. I believe that if would need to work and live in Wisconsin without attending school for a 1 year period. Granted, I don't know if this possible for you. You might defer a year. Check into this maybe with the UW Med school. They may have more info.