I think Customs Inspectors should inspect imports that might contain hunting trophies, Ivory, horns, antlers, internal organs of people or animals, or live animals. If the proper documentation is not presented for these items, the items should be quarantined until the documentation is presented.
If documentation (or an extension generated from the source nation) is not available within 60 days, the item should be added to the next “Customs Bonfire” or returned to the source nation.
I believe that current legislation and treaties permit this by executive order.