Late proto-IEan marker in Yamnaya was R1b. It is possible that R1b related to Yamnaya was also part of the proto-Iranian people, along with some other haplogroups.
Most likely non-Yezidi Kurds mixed heavily with the Parthian Zoroastrian R1a-Z93 people, while Yezidi Kurds who have their R1b from the Gutians and later Mitanni didn't mixed much with the Zoroastrian Parthians.
That makes Yezidi Kurds closer to the ancient proto-Iranian Gutians or Mitanni and non-Yezidi Kurds closer to the later Zoroastrian Iranians such as Zoroastrian Parthians or Zoroastrianized Medes.
R1a-Z93 has something to do with the Zoroastrians.