It’s a no-brainer. Take the full ride. The economic uncertainty could bite you in the butt later if you choose Brown. If a parent gets laid-off, you could lose your source of money. You have a guaranteed source of money in writing for all 4 years at OSU. Plus OSU is a great medical school, and state schools give preference to state residents. That’s, by far, your best shot at medical school.
Also, a “top school” won’t get you into a “top medical school.” Your grades and MCAT scores will. Also, you REALLY don’t need an ivy league med school to be a top doctor. Dr Ben Carson went to Univ of Michigan. Dr Russell M. Nelson (pioneer of heart/lung machine) went to Univ of Utah. I know a world renowned brain surgeon who went to UT-Houston.