So I am running HA in a container so I can't simply use the z2m addon. I installed zigbee2mqt and eclipse mqtt as a broker. They both seem to be working.
I went ahead and used the z2m dashboard to add my first device that paired successfully.
I went to HA and added MQTT integration, and it seems to connect to my broker ok... However.. I don't see the device I had added anywhere.
NOTE: When I setup z2m onboarding, I disabled the HomeAssistant checkbox because I thought that was for the add-on - would that explain it ?