Suing a Chinese company in China is a poor option in this case, even if there was an investor with $500K that was willing wager that money. I say "wager" because in China, the Chinese defends their own. Last, IF any money is recovered, the Chinese Attorney fees will eat up the amount rendered in a favorable verdict.
Sure you can sue, but you will just be feeding China more money, again!
Yes, it their system is corrupt as you yourselves experienced that first hand!
I am sure there are still some people on this board that will continue to give China money through other Chinese fraudulent stocks.