Captain Sim wrote on Apr 28^th, 2020 at 2:15pm:

This may help as well https://www.captainsim.com/cgi-bin/user_.pl?action=rescue

Seeing as an Order Number is required, can they still get it/them unlocked without one?

The FlightSimStore never stored the emails I received after purchasing any product, although they did keep a copy of the order/sale, that had the same details that the email had. Anything you buy digitally, normally comes with a strong advisdory to keep a copy, or print out a copy, of the email for if you need proof of purchase. :(