Your only other option, would be to perform a CIFS restart on the filer, to restart the service. However I dont think its an issue with the Filer. The user name and company metadata is normally within the application as nigelg1965 stated.
To unlock the files / determine who has it open, the simplest solution may be to point MS Computer manager at the filer. Assuming the customer has its own windows admin people but are not NetApp skilled.