As a temporary fix, instead of service systemd-resolved restart as per the article, you can try this, service systemd-resolved stop
Once the service is stopped the port should be free. You’ll have to do this on every reboot (though maybe you can try adding the command to /etc/rc.local to stop it on every reboot)
This is outrageous. Wonder if there are any grounds for a lawsuit - if that route is possible, then I’d expect the union to get their *** handed to them at the end of it.