It is VERY doubtful if 500 people died even with a direct hit that leveled the building. Supposedly, from what I can tell, (from 2 sources I'm not completely sold on yet), it was an 80 bed hospital. So it would be extremely unlikely that 500 people would be there even on it's most crowded day ever.

And it appears general consensus is the rocket hit the parking lot, so casualties would be even less........