Resolution:
When CIM is clustered, only one instance of FileWatcher should be running or else enable the lock file feature for FileWatcher. If this is not done, there's a chance that multiple FileWatcher instances would process incoming files simultaneously which is not desirable.

The FileWatcher can be disabled on CIM instances by setting the PollingInterval to '0'.

You can also use the FileWatcher lock feature to prevent more than one FileWatcher instance from processing an incoming file.