ZENworks Subscribe and Share Subscription fails indicating Internal IP of the Sharing Server

Adding a ZENworks subscription to subscribe to another ZENworks zone
The sharing zone server is on an internal network in relation to the subscribing server

An error message such as the following is seen in ZCC:

The wizard cannot continue for the following reason(s): ErrorFailed to connect to the remote zone server "10.0.0.35". Connection refused

Do the following in the Sharing zone:

1. Navigate to the sharing server's Summary page:
   ZCC > Devices > Servers > [click the link for applicable server]
2. Configure an additional IP address for the server:
   Settings > Infrastructure Management > Non-detectable IP Addresses

Do the following in the Subscribing zone:

1. Rerun the ZENworks Subscription wizard
2. Instead of using a zone from the Registered Zones drop-down menu, click: Register with a Zone
3. Continue with the wizard as prompted

The important thing to notice about the above error message is that in this case, 10.0.0.35 is the internal IP address for the sharing server. This internal IP address isn't reachable by the subscribing server since the two servers are on different networks entirely.