From discussion in the rh-sso-pm mailing list it seems that instruction to yum install rh-sso7-keycloak-server is incorrect due to many reasons.

Correct instruction is to install rh-sso7 using yum groupinstall rh-sso7
Server installation guide, 2.3.2
https://access.redhat.com/documentation/en-us/red_hat_single_sign-on/7.1/html/server_installation_and_configuration_guide/installation#subscribing_to_the_rh_sso_7_1_repository_and_installing_rh_sso_7_1