Hi everyone,
I think what you found here is the bug. Partially it was fixed in the mentioned BZs but later we realized it still exists under some circumstances.
I have posted GitHub PR [1] addressing it and it has already been merged. This fix is expected to be released as part of oVirt Engine 4.5.2.
After that, it will be possible to fully use SSO ie. login with the same username to grafana and oVirt. The root cause for this bug was a different 'admin' email being used in grafana and oVirt.
Until then, I think it should be possible to login grafana/monitoring portal:
1) when no keycloak enabled: use 'admin' and don't use 'oVirt SSO' on grafana login page
2) when keycloak enabled: use 'admin' and don't choose 'oVirt SSO' on grafana login page
3) when keycloak enabled: user 'admin@ovirt' via 'oVirt SSO' on grafana login page, or login first to oVirt and then go to grafana (Monitoring Panel). Last option should not ask you for credentials again as the SSO is supposed to work.
thanks,
Artur