That would be the promotion runs from the new sportsbooks. Those are very limited and very short time so you shouldn't count on it especially if it weren't run on 'safe bet' matchs.
I agree, OP should focus on placing bets on safe matches, and even more advantageous for him. in case the casino offers some bonus (it always has requirements to get the bonus) and they are games in which he constantly plays then in this scenario he can run after the bonus
Instead, it would be best if you looked for a welcome/new reg bonus, which only requires a small minimum deposit for an instant amount of money for you to bets.
most bookmakers ask for $100 upwards and also have very difficult requirements to claim the welcome bonus, with so many people who abused the welcome bonus casinos started to put higher requirements for people to be able to withdraw the bonus welcome
I think I saw yas bet that open recently have such program, 'deposit minimum $10 to get $200 welcome bonus'.

are you sure?