It's not sure the southern Veneti language was in between Celtic and Italic, it seems they were rather on the Italic side, the Latino-Faliscan one, and was an archaic form stayed longer in North in proximity of proto-Germanic (according to B. Sergent, early Italic kept in its first stage more ties with proto-Germanic and with proto-Slavic than did Celtic) ; things are not clear at all; I don't exclude first veneti being part of Lusacian culture at Urnfields times (West the Vistula/Wisla), separated from ancestors of Qw- Latins by the coming of Osco-Umbrians (P- Italics) : here I 'd need the help of a knowledged archeologist; it's possible the Germanics applied the name of this ethny to other close neighbours in Poland, a bit further East, among them Balto-Slavic tribes, or proto-Baltic and/or proto-Slavs; when true Veneti left the North to go towards South, under diverse pressions, this name, evolved in Venedi, applied later to the remnant of neighbours, possibly Balts and/or Slavs; this way of unprecise namings is common, Germanics applied the 'walah' terminology to a lot of foreign pops everywhere when at first it qualified a Celtic tribe only! (Welsh, Wallach... even maybe Gaul) - this Venedi can explain the Wend term, applied today to a Slavic group in East-Germany -