Wilful blindness would probably be regarded as incompetence or deviousness worthy of dismissal. Allowing a customer to purchase money orders under different names suggests illegal activity is going to occur. Selling multiple money orders to customers and not recording his or her id could be incompetence on the part of the clerk.
Completing a transaction for a less, non-reportable amount after a customer has refused to produced id for a larger transaction is an incident clearly designed to help a risky client by the clerk.