This thread is a great example of the Creationists mind set and ability to even frame a question worthy of serious investigation.
First, let's take a look at what the evidence shows.
There is more than ample fossil evidence that kangaroos and wallabies and even wallaroos were in Australia not just long before man arrived but rather millions of years before man arrived.
There is zero evidence of any kangaroos, wallabies or even wallaroos in the Middle East at anytime before zoos.
So the proper Biblical Flood related question is "How did Noah get the 'roos he needed to load onto the Ark to replenish those that got wiped out in the Biblical Flood?"
Did Noah build a boat and go get them?
Did the 'roos hop on water to come to the Middle East?
Maybe the God in the Biblical Flood Myths parted the Indian Ocean so that two pair (or seven pair) of 'roos could hop over to Thailand and up through Burma and India and Pakistan and Iran and Iraq?
Anyone so limited that they can only spell a word one way is severely handicapped!