$200k in Bitcoin is relatively easy to cash out without affecting the market much these days.

You can easily cash that out today. $200k is not a huge deal.

200k USD will be paid in BTC

There's more than enough volume on any established exchange. $200,000 is roughly 380 BTC at the current price on Bitstamp (~$530). If you were to sell 380 BTC now on Bitstamp there are enough buy orders for the entire sell to be filled before the price got to $525.

If you don't like BTC and other cryptocurrencies, we will be happy to transfer regular 200,000 USD to you after you win. It's up to you.

Pick a good day for brilliance.