I’m doing a similar sort of thing using fully kiosk browser’s REST commands.
So far, I’ve been able get HA to detect a line cross event from a HIK camera and then it sends the URL to a wall mounted tablet which opens the stream (more info) for about 10 seconds. It works very well!
Now trying to make a very simple UI that will let me press on picture.jpg and that then activates the PTZ shell command and open the stream (more info) at the same time.
I came across this custom camera card which has the live stream at full frame rate directly inside the card which also works but i need to figure out how to resize them or how to make them trigger a shell command when pressed.
I’m really very impressed with HA and the community, so many possibilities!
It’s ripe for a sweet CCTV camera UI/interface for wall mounted tablets but i never really learnt to properly code.
May I ask what your completely different route is?