I got a bit further. What i missed was to install an MQTT broker (added that).
I then made a backup of HA and ZHA (just for safety) and removed all Zigbee devices, one by one. The routers as the last, right before removing the coordinator and ZHA fully.
Then installed Zigbee2MQTT (and integration) and configure it to use the MQTT broker and to use my patched Sonoff coordinator at /dev/ttyUSB0.
After starting up i changed to “auto join mode” and the immediately the first devices came in! Great, it is such a please to work with Z2M. Just put another device (SNZB) into pairing, and it shows up right away! I could restore most of my network in minutes.
There is just one router in my cellar that refuses to pair the devices in it’s surrounding for an unknown reason.
In the map it looks like the renegate router (red marking) is connected to the coordinator, but this could not be the case as the distance is much to large. It should connect to the other router instead (…13b8)
It also show a “0” with the network strength
What i did was to move the router nearer to the other router to get it to bind initially. I guess it then binds directly to the coordinator, like the other router nearby. Then i moved it back into the cellar and now it can’t connect to something.