You might need some extraordinary circumstances for Australia to accept Timor Leste. This is pretty much the same time that Papua New Guinea was let go. So I think you'll need different leadership in Australia for this to happen.
But if this guy does win, then it would show that there is a desire in Timor Leste to be a part of Australia. This is only two years after the 'White Australia' policy ended so there might not be much desire for Australia to add Timor as a state.
Waving that aside though, the current population of Timor Leste is 1.3million and Australia has a population of 26.8million so the Timorese won't become a big majority or anything. However, Australia may decide to continue Timor Leste on the path that Portugual did. (funding education and promoting coffee exports) I'm not sure how much coffee can be grown there or what other cash crops can grow there. But Australia may see it as a perfect plantation. A bit more investment and it would at the very least keep people working and Indonesia won't be invading for obvious reasons. Obviously some Timorese will emigrate to Australia, but I can't imagine too many would go during this time.