The cluster nodes get their names from a self-lookup on the nodes themselves, when the naming appears wrong, it's usually because the nodes hosts file doesn't include the right details.
I suggest you look at the /etc/hosts file on each node, and if not present add a self-resolving (localhost/127.0.0.1) entry for each node. without knowing what may already be in the hosts file in your case, leave anything already in there alone.
so for example if you have three nodes named node1, node2, and node3, and your domain name is example.org add a line in each like the below.
on node 1's /etc/hosts:
127.0.0.1 node1 node1.example.org
on node 2's /etc/hosts:
127.0.0.1 node2 node2.example.org
on node 3's /etc/hosts:
127.0.0.1 node3 node3.example.org
The changes won't be picked up until after restarts, so don't worry if you don't see a change right away.
The same can be used for any Linux based ActiveGates you may have incorrect names for.
I'd be cautious with such a setup. I'm concerned it may cause OneAgent/ActiveGate communication issues, as hostnames will appear in the communication endpoint list. If the same domain is represented by multiple nodes it may cause instability, missed or incomplete data. It is recommended to have separate host names.