My girlfriend got scammed the same way but she actually sent the scammer money. For whatever reason during the first week after depositing the fraudulent checks her account showed -4000 when it should have only shown -2400. She attempted to deposit 3 checks but the bank froze her account after the 2nd one.

Bro, OP is saying that one of the checks his brother decided to deposit in OP's bank account actually got cleared by the bank... but they then retracted the money from his account, after they personally cleared it and paid him, bc it was a fraudulent check???... that's not how banks operate. They wouldn't just credit OP's account without confirming that there's a valid route to debit the payer's account...This cannot have occurred as OP said it did