Congratulations that is a positive result for you. I had no idea how much Nigerian currency (NGN) was valued against USD$ therefore I checked the rate for 3,050,000 NGN. It i equal to around $1990 USD and that is a lot of money.
We have to give credit to BC Game for returning your deposit and also give you credit for accepting your error and not trying to chase any other amounts when they offered to let you withdraw the deposits.
That being said, I count my blessings. I was able to get my deposited amount into the casino back. That to me is a Win. I did not have any reason to waste it all on the casino helplessly.