I think the only way Perez, Villar, Genord are back is 1) they don't get drafted, 2) they get drafted, have an extremely overvalued opinion of themselves, 3) love the college experience so much they want to come back for their senior year, 4) don't want to play pro ball.
Personally, I think #1 is the only possibility and I don't think that happens. But who knows.