I would be happy to Skype with your son, I'm very familiar with the in's and out's of the VFX-SD. I can give him a crash course in what the instrument can do, how things are organized, where to find things in the manual, There are several good organ patches that come stock, and the instrument is fully programmable, it's pretty quick and easy to tweak the OEM patches to get the sound he's after.
You can email me directly at danrue@hotmail.com to setup a time,etc.