From the TRAC exception task:

We should update the docs to explain how to pass customized parameters. its similar as we do it in rhoso, so should be easy to do.

The following doc is likely to need the update:

https://docs.redhat.com/en/documentation/red_hat_openstack_platform/17.1/html/deploying_an_overcloud_in_a_red_hat_openshift_container_platform_cluster_with_director_operator/index