A 3.5 is on the lower side for Goucher if I remember correctly from when I applied but I wouldn’t let that stop you from applying. There are plenty of other postbac programs that can get you where you want to go besides the big two. Best of luck to you!
You can look for established programs - many universities have them - try to find something near where you are, and that is minimizes cost (medical school is expensive enough). Another option is to just take classes at a school that fits your schedule.