What of the Lamanites,DNA.and lost tribes?

Mormons teach ,as does the opening page of the Book of Mormon that all,or mostly all mesoamerican native peoples came from Israel.(in separate migrations pre Columbus).
DNA.experts beg to differ.Careful dating studies with DNA.and family lines shows that their ancestors came via the Asia-Alaska landbridge.They migrated south and east throughout north ,central and south america.No need to belabor this one…just to say that the LDS need to rethink this one.
Can any horse,cattle,elephant bones-artifacts be found anywhere preColumbian in south America?See Simon Southerton,PhD-Lost Tribes&DNA.
-ex LDS bishop scientist.
DNA.doesnt lie in court!

If you were to bring an artifact from overseas into the US, how would you go about doing so?

My family inherited an ancient Indian sword that dates back to the 16th century. It was handed down from generation to generation for many years. My family would like to preserve a part of our family history rather than losing it. The problem is that the artifact is left back at their home country and would like to bring it here. How would they be able to bring it across US borders legally without it being confiscated by US authorities?