well instantly some bad news. i attempted another withdraw and it got instantly cancelled for "You have exceeded the maximum allowed per transaction or per time period" so maybe they have reduced once again the amount you can withdraw per month.
my old limit was 4x 50mbtc a month. i will check in with them and see what it is now
This is absolutely horrendous. Gambling itself incurs a lot of risk which successfully paid off for you, but getting the amount itself from mediocre sites like Nitrobetting adds another layer of risk.
It's pretty evident that they are trying their best to not payout your funds implying that it's a trash sportsbook through and through. All the best with getting all of your funds successfully.