Given the time between the incident and him walking away, it is possible- perhaps even probable- that Tahu went to those in senior position in the NSW camp and got nowhere.
If he did attempt to sort it out, I doubt he was stymied by any ingrained racism. It probably had more to do with the hero-worship Johns generates and the NSW heirarchy not wanting to upset their golden child.
So if Tahu tried and got nowhere, and felt strongly about what was said, the only way to force the issue would be to leave and allow the media to do its work.
If he did attempt to sort it out, I doubt he was stymied by any ingrained racism. It probably had more to do with the hero-worship Johns generates and the NSW heirarchy not wanting to upset their golden child.
So if Tahu tried and got nowhere, and felt strongly about what was said, the only way to force the issue would be to leave and allow the media to do its work.