Re: The real point
Agreed it could have been the chaps iPad and FB account. However, he wasn't actually doing it. So, how is he liable. That's like saying if someone steals your car and runs someone over, you're liable as it's your car. The person actually doing it is liable, nothing to do with the device or account involved.
Maybe they're arguing he helped facilitate the crime. However, this would mean they should sue his friend for the offence and him as an accessory. Strikes me that the case could be argued, but it's the old issue of costs becoming stupid, so easier to settle as he's done.