I don't understand why the fact that Etruscan is not related to Vasconian or Basque or Iberian means it can't be a pre-Indo-European language.
By this time, the "farmers" had been in Europe for 5,000 years. Is that long enough for differences in language to have developed?
Are Iberian and Vasconian or Basque closely related?
Plus, we have so little actual written Etruscan, I don't know how hard and fast conclusions can be reached. It seems linguists are all over the place in this matter.
Or, we could go back to the hypothesis that some R1b people, as perhaps in Spain, carried non-IE languages. Of course, we don't yet know the yDna of the Etruscans.
Are some people still writing elsewhere that there was an "elite" migration from Asia Minor and the language came from them? It would have to have been very small as the autosomal signature is not only close to Tuscans, North Italians, Spaniards, but one is close to the French.
Also, to correct a misstatement above, there was disagreement among the ancient authors as to whether the Etruscans were "local" or from Lydia.