The driver pulls the default from what is loaded in the tray, so if the Server 2012 driver is the same as the one on the client PC then the issue is in SNMP, the server isn't pulling it correctly.
So compare the SNMP setting in the port as well as the Configuration tab in the drivers on both the Server and the Client.
But if Server 2012 was using the V4 driver, or the MS Provided Xerox Class Driver, then you would need to grab the Xerox Print Experience App to get it working properly, this is just a thing with Class drivers and V4, to use them, you need an app from the vendor to gain full use.
I have Xerox C60 and WC7855.
When, i installing the driver on the local host, the default print settings = A4, and it`s OK!
But, when I instaling on the server, the default print setting = Letter.
Regional settings are the same.
What the problem?