Scribing is not clinical volunteering since you will be paid. You definitely need to volunteer, preferably in a non-clinical setting (tutor, coach, soup kitchen, homeless shelter, etc.) but another role in a clinical setting would not hurt either (local hospital, hospice, etc).
Even though scribing is pretty similar in a way to shadowing, you still need a distinct experience of shadowing. 50 hours should suffice, and try to make sure it is primary care.
Make sure your MCAT is really strong. If you want MD, shooting for 510+ is your best chance as the average matriculant is a 511 I believe. Keep up your grades as best you can.