Have a look on: https://www.askgamblers.com/casino-bonuses

The OP got scammed by one of thousands of casinos popping up the past year or so, they have RTP higher than it should be ingame(so generally every player makes a 'profit') to attempt to scam them later on by charging withdrawal fees/verificaation fees etc until they bleed you for as much money as possible before you give up trying to cashout your big win.   But yes there are plenty of legit caisnos with highroller bonuses etc where 4 figure deposits can be made with a deposit offer

Do you have a picture of the terms by chance? 

It usually takes sometime for them to review your game play - how long have you been waiting so far? 

For crypto casinos only?