My divorce decree was archived using microfiche and, shockingly, does not have a visible stamp or "filed on" date. Most people, even lawyers who submit these documents, probably wouldn't have noticed since every page is certified, but that's not good enough for USCIS. There is no way the court can retroactively reapply the stamp and file date, so they offered an "exemplified copy". Exemplified copies are more than certified copies -- the clerk certifies that the copies are genuine and the judge certifies that the clerk has the authority to say they are genuine.
Hoping now that USCIS will have sympathy and expedite our case since this wasn't our error.