Keycloak does not officially support multi-region clusters in an active-active way. The reason is latency. If you want to run something multi-region, you can only run in most reliably in an active-passive way with a failover scenario in case of an error of the active site to tear this down, and put up the passive site to become the active site. As the synchronizations of the Infinispan clusters and the databases are asychronously, there might be loss of some data/sessions.
See also a related discussion here: Keycloak active-active Docker - #5 by dasniko