That's a very narrow and biased paper. "nothing, absolutely nothing, has ever" are loaded emotional words. It would be much more accurate to say "nothing that they know of, in their interpretation, and according to the two theories they cherrypicked and considered would suggest to them, yada yada yada". They seem to consider themselves dispassionate observers, but their analysis indicates otherwise. I am always disappointed, but not surprised, when individuals who consider themselves to be scientists fail to recognize their personal bias.
There are lots of other theories, interpretations, and excavations, some obvious, that they do not consider, and which they either wilfully, or ignorantly, ignore. But that is inexcusable when they use such strong language in an obviously biased analysis, based on their personal belief. As a scientist, it is always healthy to be aware, and open, that you may not know everything, and you might be missing something obvious-- even when dealing with something that you may personally dismiss as incredible.