Previously with the redhat_register template I was able to pass in a subscription_manager_certpkg_url which configured subscription manager to use the satellite instance. It seems this should be configurable with the new commands as well.

It seems we just need to make these configurable to something else if katello is not installed.
subman_hostname = " --server-hostname #{@host.content_source.rhsm_url.host}" if (plugin_present?('katello') && @host.content_source)
subman_rhsm_baseurl = " --rhsm-baseurl #{@host.content_source.pulp_content_url}" if (plugin_present?('katello') && @host.content_source)

A side note is that the above rhsm commands are not documented in RedHat's documentation.
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/9/html/performing_an_advanced_rhel_9_installation/kickstart-commands-and-options-reference_installing-rhel-as-an-experienced-user#rhsm_kickstart-commands-for-installation-program-configuration-and-flow-control