To get through a home router to a Cisco using my STUN Quantar/AstroTAC linking method you need to forward the ports used by the STUN groups:
1994 : high priority
1990 : medium priority
1991 : normal priority
1992 : low priority
These ports are shared by the STUN groups.
I have had multiple Quantar repeaters feeding one AstroTAC using 8 ports Cisco serial adapters.
73, John ZL4JY