Hi,
Repadmin.exe examines AD replication status instead of file replication status, and file replication service is used for replicating SYSVOL on Domain Controllers and Distributed File System (DFS) shared folders.
I suggest you refer to this troubleshooting link below to troubleshoot event 13568:
Troubleshooting File Replication Service
http://technet.microsoft.com/en-us/library/bb727056.aspx#EBAA
If the issue still persists after you have gone through all troubleshooting steps, you can perform a non-authoritative store on the problematic Domain Controller to fix the issue:
How to force an authoritative and non-authoritative synchronization for DFSR-replicated SYSVOL (like "D4/D2" for FRS)
http://support.microsoft.com/kb/2218556
How to rebuild the SYSVOL tree and its content in a domain
http://support.microsoft.com/kb/315457
Best Regards,
Vicky