Apologizing in advance for saying things so elementary.
Yes, I use in a couple of routines the camera’s person detection to display the image. But I more often use the “time” to bring up a view because if/when its the only action in a routine, it usually stays on that camera and shows that view for 1+ hour.
As for your “my only issue”, there’s something in the Show 5/8 Gen 2, that makes it use PiP after about 10 minutes. I had a couple of 8 Gen 1s that did not do this, so I want help to fix the Gen 2. Three times, different days, I reached out to Alexa team with a well written narrative and pictures of what the issue was. Each time, they claimed they didn’t understand my problem or could not replicate it. At least twice, I simply did not believe the tech, and I gave up. I stay away from Gen 2. I bought a couple more Gen 1, as refurbished and warehouse returns to get them at a good deal.
In my example for you (just an example), your new Show 8 is named “Show8x”. And the camera is “Cam1x”
To “force” Alexa to run the display from a camera command, you need to use the Custom choice when adding an action. And the routines only allow us one “Custom” action choice per routine. I wish they permitted more. I suspect you already knew that, but might as well say it anyway.
The action in the Custom line is simply . Show Cam1x on Show8x. Once you save that line, the Custom action adds “Alexa” in front, so it reads “Alexa, Show Cam1x on Show8x” And, I suspect you already knew this too.
I think, if you simply use "Alexa, Show Cam1x, its going to default to the device that is in “Hear Alexa from”. So, we want to point the “Show” action to the proper Echo Show on its Custom action line, with "Alexa, Show Cam1x on Show8x. And it allows us to use a different Dot on “Hear Alexa from”.
I’ve not seen it from Amazon/Alexa anywhere, but every time I use a show as the “Hear Alexa from” It more often fails than successes, hence I recommend using a Dot or Echo, just not a Show.
I had luck with 4 cameras showing once or twice. I think the action in the routine was “Alexa Show 4 cameras.” But it was not calling a group created in Wyze. The 4 cameras is not useful to me, so I’ve not played around with it. Can’t help you there.