No, I think it's fine he published the book. What would be nice is detailed peer reviewed papers describing the location, context and nature of the finds.
Those are still secondary to the actual material itself. Until that is there a real conclusion can't be arrived at.
I don't really deserve much of an opinion on this. I have only looked at the pictures posted here. To me they are enormously unconvincing. But I maybe missing the best ones. Also I know squat about the time period or the cultures involved. It's just awfully flimsy for making very big statements it seems to me.