To turn into dust?
>They could also sell into USD on exchanges that allow you to trade USD (e.g. Kraken).
And trust Kraken then.
>Another option would have been to open a hedging short position on say, Bitmex.
and trust bitmex then.
There are no scalable options to cash out $10m to a bank and sleep well. You could cash out into some "stable coin" only to wake up to it costing $0.04 (hello nubits). Tether is no safer in that matter.