Except for the Educational Component

There is only one reason to figure out who was involved in something that went wrong, and that is to let them know so that they can help figure out how to prevent the problem in the future. If you assume that they would not have done it if they knew it would lead to a bad outcome, you can present it as a question in logic and not an accusation. Then people are glad to investigate and see where the misstep was, usually a defect in the procedure or the implementation that seemed right at the time.