Well, Square Enix regularly updates the current server population every six hours or so on the Lodestone, so that can give you an indication on whether it will be possible to create or transfer a character to your server. This was the most recent post in regards to this: http://eu.finalfantasyxiv.com/lodest...23e07acb3d22f6

Interestingly, it says your server (Sargantanas) is currently open, so it's possible your friend might be able to get on now. If not, just keep checking the Lodestone regularly for updates on server population. Good luck!