You can trust Zhou with your name just like you can trust him with your bitcoins.. Oh...
Seriously, Maria, with this amount of money at stake don't argue with a kid over a web forum. Get a debt collection agency involved and give them all the information you have. These people are experts at collecting money from people who don't want to pay and they will take a cut from the collected amount so it's not going to cost you anything up front.
I beg to differ, for my sister's first husband owes over $100,000 to various entities and has been pounded by debt collectors for
years decades. Guess how much they were able to get from him? Wait for...$0 USD or in BTC, as if you didn't see that coming.
Debt collectors don't always win but they have better odds of getting your money back than any other legal means.
I never said I was 100% certain it would work but arguing about it on an internet forum isn't going to settle anything.