I find it suspicious that he went from fraud in a hedge fund Tiger Asia involving manipulated prices and insider trading (for which he was convicted) to a less regulated family office using things like swaps which avoid oversight, and which he then proceeded to blow up with excessive leverage (and possibly other illegal shenanigans to manipulate prices), using instruments which avoid oversight on stock positions, most likely using leverage he obtained by lying to banks about his exposure - I sincerely doubt the multiple brokers were aware of just how much exposure he had and how concentrated it was, and they all raced to call it in when they found out.

I'd be very surprised if there were no illegal activity there which would not have been caught by increased oversight, though of course it is now in nobody's interest to look into that too closely.