>>He was accepted into several, and will make a final choice soon; not sure which way he is leaning.
If he is accepted into several medical schools, then clearly he is very intelligent. Seems to me that anybody who can get accepted into multiple medical schools is a desirable enough student that he should have no problems getting a partial or full scholarship, thus bypassing the whole "National Guard to pay for Med School" issue.
Unless he were in an education/commissioning program, I can't see how he could possibly juggle Med School and Guard obligations simultaneously anyway.