Yeah, Zappa's name is dropped but he really had absolutely nothing to do with this. In the link you gave, it merely happened to be the case that Zappa was at a festival at which Amon Düül, Tangerine Dream and Guru Guru performed. That's a bit like pointing to some particular at Coachella or Glastonbury and finding that both Beyonce and Chvrches performed (i.e. the only connection is being in the same place).

Zappa's own explorations are amazing (watch parts of Live at the Roxy to get an idea of his ensemble at its best, and there's oodles of other incredible rock-infused-with-jazz-and-classical-understandings in his output), but they really have essentially nothing at all to do with the evolution of techno.