All that should need to happen is that the DNSOnly system gets added to the cluster on each webserver, and then you perform a sync from each webserver. I would run "/scripts/dnscluster --syncall" on the webserver to ensure those zones get updated to all the DNS cluster members.
The wording around the different settings in the DNS clustering function is still confusing. This hasn't changed in years.
Synchronize Changes: All changes made on this server will propagate to any server in the cluster that is linked to this server. Synchronization is one-way: changes made on another server will not propagate to this server unless Synchronize changes is selected on the other server as well.
Standalone: No changes made on this server will propagate to any other servers.
Write-only: This server will write changes to the remote server. Changes to the remote server will not propagate back to this server. Warning: Two Write-only servers that attempt to write changes to a matching record on the same remote server will cause a conflict and may corrupt data.
The cleanest scenario one would be on WHM-Server with two DNS directly linked in the DNS cluster settings.
The "DNS Role" in the dialog is defining the role of remote server when interacting with the logged-in server.
When I chose e.g. "Standalone" for ns1 and "Write-Only" for ns2, the DNS role descriptions are
I would change the description to "Standalone : No changes made on this server will propagate to the remote server."
The "any other server" is misleading, isn't it?