In the last publicly available documentation[1] we're referring to sso75-cpaas-dev branch[2]. This branch haven't been updated for 6 months. All the recent commits are available in sso75-dev[3]. Just for the sake of completeness, here's the place in the prod-docs[4], where the inaccurate variable propagation is happening.

[1] https://access.redhat.com/documentation/en-us/red_hat_single_sign-on/7.5/html/red_hat_single_sign-on_for_openshift/get_started
[2] https://github.com/jboss-container-images/redhat-sso-7-openshift-image/tree/sso75-cpaas-dev/templates
[3] https://github.com/jboss-container-images/redhat-sso-7-openshift-image/tree/sso75-dev/templates
[4] https://gitlab.cee.redhat.com/keycloak/keycloak-documentation-prod/-/blob/15.0.x/openshift/topics/get_started.adoc#L55