I have to admit I was surprised with the speed with which your exchange is resolve this issue, this usually takes weeks or months - and some exchanges do not want to deal with such things. What's even stranger that you use fake wallet for BCD and that wallet did not steal your BTC, but only send coins to BTC address instead to BCD.

Anyway at the end it is good that you save your coins, but always use only official wallets and before claim of any fork coin move your BTC to new wallet.