Question? If he/she was selling off there coins and not investing them in something else wouldn't they put it on an exchange like Coinbase where they can cash out instead of a exchange that doesn't offer withdrawals to the bank? I'm still learning and this might be a stupid question but I have not noticed anyone asking it so thought I would.
If someone is indeed interested in a big cashout without leaving a lot of traces, they would not cash out to a bank directly. Instead trade it in small batches for Monero or some other privacy coin. They would then move those coins around a bit and finally deposit to another exchange (or multiple exchanges) for encashing in batches of fiat. And if that guy is money laundering at all, it would also mean that he will lose about 30-40% of his wealth while doing all of this since he would need multiple parties to be intermediaries in this entire operation to hide his trail. Let's see what happens. Probably movement in prices of privacy coins will give an indication in the coming days.