I assumed it was through WiFi, I’m guessing you’re running it through Thread. Is it a standalone or is it connected to some device, maybe you can access it through the device it’s connected to? There might be a program for that.
I’ve got mine on WiFi (not through zbt-2), and it does indeed have a webserver that HA connects to
It needs the official google home thing. But you can still access the Matter controller webserver. Assuming it’s the same WiFi your phone/desktop is on, you can find out what it’s IP is and what the address port route should be (from their docs) and it should work.
I’ve had the exact same issue and still managed to add my robovac to it (running HA on an old laptop, the “controller” is just another docker service running on that laptop)
Well HA is able to talk to it, I assume you can access the rp machine and do the same to accomplish your goals.
I hope this info, helps, sorry I couldn’t help further