I don’t have an answer, but I’ve always found the camera viewing within Google Home to be hit-or-miss.
What I’m seeing right now is that if I’m looking at the home screen of the Google Home app (Favorites tab), the Categories section at the top shows “8 cameras” on the Cameras tile. If I tap that, then after a few seconds my cameras begin to load, and I’m able to scroll through and see feeds from all eight…most of the time. Four of the eight are Cam v4s. If I tap on an individual Cam v4 tile, then I get the “Connecting” message for a while until it eventually times out and gives the “Live video unavailable” message with an option to “Retry”, so that’s a failure, and I’m not sure why that would be the case viewing an individual camera when they load as a group (but I see something similar in the Wyze app itself pretty frequently).
Even the Cam OG, which has been one of my most stable, even working through a recent apparent “outage”, is a little spotty with this today, but that’s what I’ve come to expect with Wyze’s Google Home integration.
I think you’re doing the right things, and I don’t think it has anything to do with the Cam v4’s firmware (I’m on the same version with my Cam v4s), but I’m not certain about that. I think it’s more of a Google Home thing.
Like you, I would’ve reconnected my Wyze account through Google Home and would’ve also said to Google Assistant, “Hey, Google, sync my devices,” probably prior to trying the account reconnect.
I appreciate your mentioning Amazon Alexa, because I’ve just recently connected my Wyze account to that so I can have dual-assistant control for devices, but I hadn’t yet tried streaming cameras through the Alexa app, so it’s cool to know that this works. I hadn’t tried that before. Thanks!
One thing you could consider trying: If you’re using the standard version of Google Home currently, then you could enable Public Preview (Settings ➜ Public Preview) to see if that makes a difference. When I tried that just now, it let me view my Cam v4s individually, even after I left Public Preview and went back to standard. I mention this because in the past when I’ve had Public Preview enabled, I’ve been able to stream some other third-party camera feeds in the Google Home app that I wasn’t able to see in standard mode, though today even enabling Public Preview isn’t making those work (not a big deal; I can still see them on connected smart displays).