I don't know who planned the whole operation but it was some pretty dumb planning. I mean if i were attacking ORB knowing Djibril was there, i would take into account the fact that he was definitely gonna try and escape when ORB's position was unfavorable. Hence there should have been 1 or 2 Zaft fleets patrolling space in line with ORB just to make sure that Djibril didnt get away and shoot him down once he exited the earths atmosphere. I mean its not that he immediately teleported to requiem as soon as he entered space