Obviously, first make sure the user is using the correct workgroup and is logging in as the expected user.
Beyond that it depends on if you have another copy, backup or original information you created your workgroup with.
With a copy or backup you can replace the file, but passwords may be different in the different workgroup.
With the original information, you can simply create a new version using the same pids, passwords will have to be set again too.
Finally, you can assign the admin user permission to read design and read data everything, create a new workgroup file, import everything as the God user and set permissions again. If you are here let me know and I'll see if I can't find code that will help.