You don't understand forensic computer science very well and so far the thief doesn't appear to either. This thief is moving a HUGE amount of mostly very traceable money.
One little slip up with ALL that money, just one, and/or one little assist from those with a "grasp" on TOR and what not  , and he is caught. It may happen now, in a few months, or even years.
But, I'd say he is as good as caught.

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