Official comment
Currently, we do not support Authorize.net's fraud detection suite. If we get anything except a "successful transaction" notice from Authorize.net we mark the transaction as failed.
You can add a step to your manual process with Authorize.net. After manually approving the transaction return to ONTRAPORT and add a manual transaction to the Contact. You can "Log a Transaction" without charging their card again, and back date it to the original failed transaction date.