This is an anti-fraud mechanism which should only be triggered when there are fraud indicators. Those usually have to do with purchases in high-fraud areas or CC's from other jurisdiction. Neither the case here.

The passport is one thing (as they will see that and could well take and store a copy at check-in), but the CC statement is another.

This is more than likely an error. Call before sending anything. If there is some other odd trigger, perhaps you can explain that on a call as well.