@nickrout , I have a VSX-LX503. It uses the old pioneer interface, not the (far more sane) Onkyo one.
In trying to answer the integration question, I realized I’m not using a Pioneer or Onkyo HA integration at all. HA automagically found the Chromecast capability of the receiver. That’s what I’ve been playing with. I have, however, also been trying to get any of the actual Pioneer/Onkyo add on integrations to work, but none seem to be able to communicate with my model. So, obviously I cannot tell the HT receiver to use Zone 2 anyway