Something you might check is the Bonjour service in the router. If the router doesn't support Bonjour services, you will not be able to use it to print from any apple device via AirPrint. You can still print from a Mac PC if the drivers are installed, but you will not be able to print from any iOS device. You can use the app below to test the network to see if it will alow Bonjour services. Let me know what you find.
I am a printer tech for HP.