Only 18 participants have received $20 prizes. The top 50 players have received minimum $50, which is above the min withdrawal limit. Maybe you haven't checked the prize distribution list . I have participated in the competition and won $50 from it. Although my balance was withdrawable without any condition, but I have placed some bets to test my luck. Then I had requested for a withdrawal. Anyway, OP has taken an action for those participants who has received $20 prizes. Therefore, those participants don't need to play the games if they don't have the habit of it.