Claim the return for the deposit (DEPOSIT_RETURN), then cancel it. The
amount is the only key, so the candidates are recomputed here, not trusted.
Only a definite refusal releases the claim; an unconfirmed or interrupted
cancel keeps it, so no other deposit can take the return while it may land.
Same-amount ACH debit deposits whose batch went out in a NACHA file. fail
refuses a live one whose hold ended, and a PENDING one bar a pre-patch run
(DEBIT_IN_FLIGHT). cancelledByThis names this return; released minted.
A MetCap ACH return settles from its bank transaction: its only key is the amount, so the operator picks the returned deposit and this cancels it.