Answer
If a specific customer's underlying print-related setting appears stuck (not actually taking effect even though it looks correctly configured), try toggling it: uncheck the relevant setting on the Customer record and save, then re-check it and save again, before creating a new Customer Order to test. This has resolved cases involving a very old customer record carried through multiple upgrades, where the setting appears correctly configured but doesn't seem to be applying — re-saving after toggling it can refresh whatever stale state was preventing it from taking effect, even without a clear explanation of the underlying root cause.