these may seem innocuous enough but there’s also “immi dob-in” (for immigration offences), and “dob in a centrelink cheat” (welfare fraud).
a dobber is not a whistleblower. a dobber is a rat, a tattletale, a snitch, a squealer. if you are “dobbing someone in” you should be ashamed of yourself.
if you are using working-class Australian slang while exactly reversing its connotations to promote collusion with the State and the hard Right as if it’s part of an authentic working-class value system, you should also be ashamed of yourself.
for myself, I’m bitterly shamed by just how easy it was to kill whatever faint grounding in reality there was in the australian self-image as anti-authoritarian.