I talked to a couple of space law experts to find out what to even advise the farmer on this. I had sort of thought that since it's in another country and it fell on private property, it belongs to the property owner.
But it is much more complicated than that, because of the Outer Space Treaty.
What *should* have happened is Global Affairs Canada should have contacted the US State Department, who should have contacted SpaceX.
But I think what actually happened was someone somewhere else in the Canadian gov't saw a news interview and told SpaceX.
The space law experts I talked to agreed that since SpaceX has now asked for it (assuming it *is* SpaceX), the farmer has to surrender it. BUT he should ask for compensation.
If there had been damage, the US gov't would have had to compensate the Canadian gov't, but because it's a private company, and no damage happened, compensation is voluntary