It is hard to say anything from information provided in this ticket. On the first screenshot I can clearly see that `post_logout_redirect_uri` is missed. It means `get_logout_uri` is called without it. On the second screenshot we can see some SCIM error during searching the users, not sure whether it is related or not related to the problem you are describing.
Therefore for further investigation please attach to this ticket:
1. `oxauth.log` file
2. `oxd-server.log` file
3. identity/oxtrust log file
Thanks in advance,
Yuriy Z