rubber duck debugging to the rescue again..
By default, netmaker will forward all DNS requests to the server. If you want to use an external or private DNS server, you need to change the following config (e.g., in your docker-compose.yml on the server followed by a docker-compose down and docker-compose up -d):
PORT_FORWARD_SERVICES="dns" --> PORT_FORWARD_SERVICES=""
https://docs.netmaker.org/external-clients.html
very. last. line.