Your bank can and will help you out, that's why I suggested it. If they don't allow the bank to put the money back on your account, they can take legal action against SE, which would be more trouble then they want. For an extra laugh, you could tell SE about your plan first. Tell them that you either want your account back that you paid for, or you'll take it further. That way they'll be forced to send you over to the higher-ups, which have more flexibility and control, which could hopefully help you out further.
Edit: I'd still like to know when their accounts got stolen though. Was is before or past 1st of September, and if it was before, did they still get charged September 1st? If they did, best case: They could involve the police and file for financial identity theft. Worst case: They could involve the police for stolen goods and stolen credit card information etc, which is basically financial identity theft anyway, but divided in to smaller parts ~.~ In either case, they should be able to make SE give out information about the thief. Although I'm not entirely sure how that works for cross-nation, since Harb is from Sweden =/
Edit: The company I work for get several attempts from people buying our merchandise with stolen credit cards every week. Sadly, the police (at least in Sweden), usually only considers it a stolen credit card and not financial identity theft, since we find out about it before they actually "buy" stuff, which is sad. And usually in these cases, the police puts the case aside in order to prioritize heavier crimes. The amount of online financial identity theft cases per year is so high that the police usually don't bother with it. Just thought I'd throw that in to not get your hopes up too high.
That being said, I still think you should go forward with it. At least then you can't complain about not trying. If you don't take any action at all, nothing will happen and you'll be in this situation anyway at the end of the day. If you do take action though, there's still a chance you'll get your account back. Although I guess this opportunity could be used to just quit the game altogether.