Damn, they never even tried to calculate their CG? That is something that will never happen in airline ops. However, miscalculated CGs do happen, very rarely though. The Lufthansa 737 QC comes to mind where they loaded several tons of freight in supposedly empty containers putting the CG way out of the forward limit, still the thing flew, although they had to use stabtrim to fly it.
A real concern however is the use of generalized standard weights that are most probably too low.