Actually you can see that every time BNB burns a coin, the price will increase 2x, 5x, 10x and you can see it when you trade on some of the top exchanges. But the price of BNB will still follow the movement of BTC price, as you can see right now, After the Burn is done price goes up quickly, and at the same time when the BTC price goes down, the BNB price goes down.