Read the paper, but the author fails to put the problem "Rhaetians", and this is a heavy deficiency.
What do you mean by put the problem? ... do you mean solve the problem? What exactly is the problem and why must it be solved? There must have been many, many non-IE languages out there in pre-historic times?
To put the problem is to be conscious that the problem exists and not ignoring it. Why there is in Italy a language (or a group of languages) similar for many aspects to Etruscan but almost different to have no recent relatedness? The author mocks Italian linguists of first size who have supported the autochthony of Etruscans (Pallottino etc.) or better the "formazione" of Etruscans in Italy, probably from many contributions, not excluded one from Asia Minor. The author seems to me a greenhorn. Being I an Etruscan, also genetically beyond my millenary Tuscan rootedness, I think I can speak on this.