I'm conflicted with this one.
If we return it to a country of origin that has no protections for priceless artefacts, we lose an irreplaceable part of our heritage as humans if the piece is lost/sold/stolen or worse destroyed. Granted it may be that country's right to decide what it does with its history, but its unfair to the rest of us when we lose our shared history because of incompetence.
Like the Buddha statues that were destroyed by the Taliban,
https://en.m.wikipedia.org/wiki/Buddhas_of_Bamiyan
As impractical as it would have been, I would much have preferred they were excavated and shipped to a safe museum or city somewhere, than being destroyed by ideological bigots. We lost an important piece of history, architecture and craftsmanship that day.