There are a couple offshore companies that let you buy/sell stocks with Bitcoin semi-anonymously. The problem is you can't short, so your attack has to result in pumping the stock: "Taking Twitter private at $420 a share".

You don't do it by selling TWTR one minute before the hack.

You use your brain a little. You prepare your positions months in advance, and hedge out market risks.

You can also use less regulated brokers in far away places and trade TWTR derivatives.

Ok but brokers aren't less regulated, exchanges are, and Twitter isn't traded on every exchange.