Smart and dumb ways to handle $ when selling my rv

I had this same discussion with my daughter in law bank branch manager.
Once a cashier's check has been cut, the account from which it has been written from is immediately (electronically) debited from that account.

You (account holder) cannot just call the bank and tell them to cancel that check.

The uncashed check must be returned to the bank by the account holder before any consideration is made to credit back those funds.