GRE : Analyze An Argument - 2

Woven baskets characterized by a particular distinctive pattern have previously been found only in the immediate vicinity of the prehistoric village of Palea and therefore were believed to have been made only by the Palean people. Recently, however, archaeologists discovered such a "Palean" basket in Lithos, an ancient village across the Brim River from Palea. The Brim River is very deep and broad, and so the ancient Paleans could have crossed it only by boat, and no Palean boats have been found. Thus it follows that the so-called Palean baskets were not uniquely Palean.

Write a response in which you discuss what specific evidence is needed to evaluate the argument and explain how the evidence would weaken or strengthen the argument.

Response : 

The evidence presented in the argument is superficially imposing the impression that the woven baskets were not uniquely made in the village of Palea, given the fact that those woven baskets characterized by a particular distinctive pattern which have only been found within the village of Palea. But the finding of another "Palean" basket in Lithos supports the fact that the baskets were not uniquely Palean. The argument is flawed at various levels due to lack of information and assumptions. 
The Brim river is the pivotal issue in the argument which suggests the point that river is so deep and broad that Palean couldn't  cross it without boats, but there are various possibilities which are not considered. It might be possible that the river was shallow long ago so that it can be without a boat or it was non existent at that point of time. No details about the width & depth of river are mentioned. It may possible than  Plean could had constructed a bridge to cross the river.  
The boat used by Plean may be very different from the general conception of boat, which the archeologists might not have identified as a boat. It can be the case that the boat of Pleans is not yet been found, still hidden from the sight of archeologists. There is no fact mentioned about the weight of the baskets,  Usually baskets are lighter, so they might be flown to the opposite bank due to flood or might be transported by other natural forces or natural calamities. The argument does not covers the social life of Paleans, it could be possible that they believed in spreading the knowledge and skills and they might had been excellent swimmers who swam across the river & taught the skill of making woven baskets to the people residing in Lithos. 
Considering these possibilities, the notion of proving that the Palean baskets were not uniquely Palean, seems to be a fallacious inference from the argument. The argument expressed by the author is weak  and lacks details about the river, people of Palea and the basket with reference to the particular era of Paleans. Without these concise information, we cannot prove the conclusion of the argument.