Are you sure that GO puts up the dialog? I think on the OSI puts up the dialog for AirPrint. Could that it?
If you want to print form the server side you will need either to 1) set up a robot printer ( This is an machine running with FM which checks a print queue table at your solution and spools the print jobs)
Alternatively 2) You can use php and fpdf to created at pdf file which which you can be put in the standard print queue (With a finder script, applescript or shell script. )
Yep, not pretty.