You need to sit down and honestly ask yourself will I be happy at this DO school? If Yes then pay it. If No then don't pay it and reapply to schools next year. However, next year don't make the stupid mistake of applying to schools that you're not going to be happy with.
Most people will tell you MD vs. DO is not a big deal and they are the same thing which is true to some degree. One day if you're going to apply to specialties like ENT, Dermatology, Plastic Surgery, Orthopedic Surgery as a 4th year medical student then having a MD behind your name will definitely make a significant difference. These specialties are extremely dense with MDs. Almost everything else you'll be fine as a DO.
FYI no one start trolling about MD vs. DO because of my post. My post is strictly to help the posters understand what they are getting themselves into.