Good business practice would at the least announce via auto-responder that the office is closed, with an automatic, respectful reply notice to anyone emailing in.
Sadly, the ( qualified) "opinions" on print-ability are worthless to you, it seems . Only admin HQ can opine, or, accept/acknowledge on your replacement image.
All the more reason for a form-email to say the matter will be addressed Monday, and, take the pressure off the artist.
Reply to the email/announcement, including your new upload, and the Order Number.....it's all you can do.