Hi @ranchuk
I am sorry to hear you still experience issues with the federated logout.
If the above implementation did not help, I can advise you to attempt integrating Single Identity Logout for your application.
You can review our Knowledge Article about SAML SLO and also our documentation about it.
Otherwise, your implementation should do the trick in logging out the user and the issue might be on Google Workspace’s end due to the fact that they might not handle the returnTo parameter in order to logout the session with them. I would recommend to investigate this the documentation available on their website ( if they provide any).
Let us know if SLO did the trick or if you have any other questions.
Kind Regards,
Nik