I'll reply on both isuues:
Per the social security tax, the school handles all the paperwork, so sadly there is nothing for you to do but sit and wait. It took one of my former co-workers 6-ish months to get it back. But she did get it back (it was deposited into the sdame account her salary was deposited so it was a good thing she kept her chinese bank card in america.
And as for who to complain to, the best solution I've come up with is the headmaster of the school. It's a huge face-losing move for the dean of the international dept which is usually enough incentive to make them do what you want them to do. I've only employed this technique once, and we had all the foreign teacher going to the headmasters office together. Even if he wasn't there, we were gonna demand to talk to somebody and was gonna make a big "foreigner style stink" until we did. But our dean heard about it and immediately backed down on our issue despite over 2 weeks of her refusing.