At least some inaccuracies have been said about the history and the Sardinian language.
Western languages all originated from a single language spread throughout the Mediterranean basin which formed a huge globalized area, the Sardinian-Sumerian-Akkadian language.
Therefore Sardinian does not derive from any language, not even from the Latin language, in case it is the opposite. It would be like saying that the son taught his father to speak.
Let's take an example that can be infinitely replicated on other lemmas. The Latin word PECUNIA, which is also used in the Italian language, derives from the Sardinian PEGUS, which means head of cattle.