Stephane-
Your arguments are accurately strong. However, the court of public opinion will weigh differently. And speaking as someone with close family ties to the continent I can tell you the fall out for JWs is exponentially worse than any law of the land could compel.
This is no accident and the commission knows very well how its agenda will ultimately hurt the JWs (and others like them) bottom line across the states of Aus.
Revisit this theme in 5 years time and I assure you the JWs wont be a blip on the map of organized religion on the island.