Ignorant American here. Isn’t Hong Kong supposed to be the HQ/money exit point for Chinese organized crime? And HSBC is the main bank there, but headquartered in the UK?
If I had to guess they are heavily involved with spooks and foreign assets operating in China (and if so, why not use them for non-Chinese intelligence-financial shenanigans?) and a lot of their “illegal” activity is unofficially blessed by foreign intelligence.