Straight from the RTC Website itself -
Outdoor photography and videotaping is not
permitted onboard RTC. The graduation ceremony is
held indoors, so ample photo taking is permitted in the
ceremonial drill hall.
Meaning, indoors (in the drill hall where your ceremony will take place) they can take pics & videos all day long. But when you leave they have to wait till your off base (if u have a day pass) to take pics.
hope that helps!