NSF (I imagine...) is against Direct Entry Captains because there is a growing army of fully qualified SFOs at EZY who are ready for a command. The only reason for the company to accept DECs now would be because they are being offered a B scale contract.
NSF would have been accepted as a DEC when EZY were expanding faster than their SFOs could pass the command course.
"One rule for him etc etc" is a bit too simplistic I'm afraid.