This specifically says:
"Temporary airspace restrictions will be active on certain days and at certain times. When the restriction is active, you must not operate your drone anywhere or at any height within the temporary restricted area. These restrictions apply to drones of all sizes and weights, including drones that might be considered small toys."
"These restrictions apply from surface level to 1000 feet above ground level."
https://www.casa.gov.au/aircraft/sta...onwealth-games
"3.5 No sport or recreational RPA, unmanned balloons and rocketry operation will be given a permission to operate within any of the TRAs as listed in this AIC."
http://www.airservicesaustralia.com/..._24MAR2018.pdf
This mentions "You must not fly your drone higher than 120 metres (400 ft) above the ground" but also says "You must not operate your drone in prohibited or restricted areas."
https://www.casa.gov.au/modelaircraft
All seems to state fairly explicitly that you can't fly at any level in the TRAs. Not that I have anything to base this on but I very much doubt the authorities would pursue someone flying their RC helicopter in their own backyard below fence height.