Just to check, because this passage is confusing me: you are aware that
- your ZigBee coordinator communicates with zigbee2mqtt only
- zigbee2mqtt communicates with your MQTT broker.
- openHAB communicates with your MQTT broker.
So your ZigBee coordinator never communicates directly with openHAB, and there is no configuration of your ZigBee coordinator in openHAB.
If this is a question about how to configure zigbee2mqtt with your coordinator then you may have more luck requesting help from the zigbee2mqtt project.