Hi,
It sounds that it should pair then. Let's try pairing from both sites as a first option. Try to establish pairing from one of the sites to the other and then vice versa. If it does not work then uninstall both SRM servers, verify from VC mob that there are no SRM extensions registered to any of the VC servers, delete any SRM solution users if any from both VCs under Administration->User and Groups->Solution Users delete any SRM-* users you see and then install both SRM server using Administrator@vsphere.local user.
Let me know what happens.
Regards,
Nik