I've only seen SFTP or FTP, I haven't ever seen FTPS anywhere on a Xerox machine. What kind of server are you scanning to - being that you asked about FTPS I'm assuming not to a Linux/Unix configuration since you would be able to use the SFTP.
I have a customer that requires Scanning over FTP using SSL. Not SFTP over SSH. I have looked through the Embedded web page in the connectivity and security sections as well as trying different combinations within the actual scan template and am at a loss. Is this something that is supported on these devices or is it just SFTP over SSH?