You are asking the node to form a new cluster on its own here:
If you want your node to join an existing cluster, you shouldn't be setting this. From the docs:
This is only required the very first time the cluster starts up: nodes that have already joined a cluster store this information in their data folder and freshly-started nodes that are joining an existing cluster obtain this information from the cluster’s elected master.
See also these docs:
When you start a brand new Elasticsearch cluster for the very first time...
I don't understand this, because I don't think that there is a mechanism to match node IDs to IP addresses and reject them like this. What do you mean "rejected"? If you're seeing messages about this in your logs, it'd be good if you could share them.