Hey, the user-name does not depend on the server, the database is residing on, but solely from what is defined inside the ID-file, that resides on the client-workstation, so if you change their names, they have to change ID-file or they have to be renamed by the appropriate administrative process, so what you did does not make sense in my eyes.
And, you are referring to the names in its abbreviated form. Do you have the names in canonical form in the readers-field? That is
CN=user/OU=123/O=Organisation ?
They have to be in canonical form to work inside readers and authors fields