Answer
No — IFS Product Development has explicitly confirmed that running IFSAPP-IAM or Keycloak isn't supported for Apps10. On that track, the supported authentication methods are limited to AzureAD, ADFS, and standard database authentication; Keycloak-based OpenID Connect (or Kerberos) isn't an available option there. This is specific to the Apps10 track — check current documentation for whichever IFS Cloud release you're on, since IAM/authentication provider support has continued to expand over subsequent releases.