Really, if you are so afraid of fungus growing in your lens, the only solution is to keep your camera in the dy box or dry cabinet forever.
Now, a slight problem, you won't be able to use your camera if it forever in the dry box.
At the end of the day, if you are using the equipment, the chances of fungus growth is greatly reduced.
Other ways to avoid fungus growth are to never travel to humid locations, leave Singapore, give up photography ...
At the end of the day, don't worry about Australia. Just bring your camera and shoot. My lenses and cameras survived many places wetter than Singapore. Wipe them down every evening, keep them in an airy location, and enjoy the trip. Or, leave the camera at home in the dry box!