The eligibility rules for the draft are ...
(A) Resident of the United States, Canada, or a U.S. territory such as Puerto Rico. Players from other countries are not subject to the draft, and can be signed by any team. check
(B) Have never signed a major or minor league contract. check
(C) High school players are eligible only after graduation, and if they have not attended college. with GED he could claim he graduated and he would not have attended college
(D) Players at four-year colleges are eligible after completing their junior years, or after their twenty-first birthdays. The exception to this is Division III schools, where players can be drafted before their junior year. does not apply
(E) Junior and community college players are eligible to be drafted at any time. that's how he gets eligible, enrolling at a JuCo