The expensive version is the one nobody sees coming
The package comes in incomplete. Nobody catches it. The part goes into stock and sits there. Six months later a customer finally orders it, someone pulls the file, and the mill cert was never there.
Now you are chasing a vendor who has stopped answering. Your customer is waiting. And you paid that invoice five months ago, so you have no leverage left.
So you eat it. Dead inventory, an unhappy customer, and a week of somebody's life spent on emails.