Insert File Name Programmagically

I'm using PDF Creator in an application that is operated by remote users using Remote Desktop Services (RDS) in Windows Server 2008 R2.  The PDF, which the user generates as a report via my application, needs to be saved on the remote users shared location, and is subject to change.  I can't use a static file name and then copy the resulting file via my application because the user may generate several of the files and if they have the same name, they'd overwrite each other.  I tried using a token, but can't find one that my application could subsequently identify.

The users shared drive shows up in the remote session as "\\\\tsclient\\driveletter , where driveletter is the shared drive and subject to change by the user, and may be different for each RDS user.  When an RDS session is initiated, my application stores the user's shared drive letter in a table, but I can't figure out any way have PDF Creator fetch and insert it into the file name before storing the created PDF file.

Can anyone tell me how I can accomplish this?