[Singh]

That looks like the Victorian high country, Billy goat bluff?
Good luck, enjoy the adventures
Don't know why you wouldn't take the Touareg over Prado for outback.
for coastal roads watchout for the road trains and windscreen damage they can do

 

[Singh]

From how I see it now, low range and diff locks are good to have, but in most cases you can, unless you are going bush bashing up a gnarly, rocky trail, it's not a must.
Look at Billy goat track, the Touareg does it without low gear or lock without any issues...
For all outback tracks, all you need is a comfortable, high clearance, four-wheel drive, better with a snorkel than low gear