My guess is that they disabled the z-wave on the Australian hub on purpose.
See discussion Smartthing Hub in Australia?
The frequency that z-wave works on in the USA is illegal to be operated on here in Australia. The z-wave frequency in Australia is different. http://www.smartesthome.com.au/article/what-is-the-most-popular-z-wave-smart-home-platform-in-australia
I am in Australia and waiting and waiting for Samsung to bring out the ST Hub with the Australian z-wave frequency so we can purchase and use Australian z-wave devices.
Unfortunately got my hopes up and looks like the Australian hub from RACV is just the USA one with z-wave disabled 