Yes, he is eligible for a free college education, as are any other qualified applicants that meet the standards and survive the selection process. When he signs on the dotted line, commits to the deal and shows up for his first day, he's locked in.
Isn't it nice there are intelligent, patriotic young men willing to give eight years of their lives in service to their country in exchange for an education that will also be used to serve their country?
His proud father was happy to, and actually offered to write a check for the entire $200k tuition and expenses that VMI commands for a four year degree, to no avail.