In OCP environment a client might communicate to a RHDG cluster in the same or different namespace for the same OCPcluster and across clusters.

Using different clusters must use the Routing which needs the ClientInteligence.BASIC

If running in the same cluster it depends on the restrictions whether the internal IP addresses are available and the Service can be used.

For this a paragraph like followed should be added
~~~
Please, take into account that your Openshift administration may set restrictions in the communication between different namespaces using the service URL. This restriction is achieved using NetworkPolicies. For more information, check the Openshift official documentation: https://docs.openshift.com/container-platform/4.9/networking/network_policy/about-network-policy.html
~~~