Reading the Emirates T&Cs, (sourced below), australian destinations all seem to have this caveat:
Maximum capacity per sedan is two adults, with a total luggage limit of two suitcases plus one carry-on bag. Additional charges apply if a larger vehicle or child or infant car seat is required.
This does seem to imply it's available.
Once you've booked it, give the service provider a call, and a heads up, they should be able to elaborate further.
chap6595
chap6595
Qantas - Qantas Frequent Flyer
Member since 17 May 2015
Total posts 41
We have a 5-month-old next month and we are travelling to Manchester.
MRYJDrake
MRYJDrake
Air New Zealand - Airpoints
Member since 31 Oct 2016
Total posts 206
Hi Chap,
MRYJDrake
MRYJDrake
Air New Zealand - Airpoints
Member since 31 Oct 2016
Total posts 206
Source: https://www.emirates.com/au/english/experience/chauffeur-drive/
obanpointer
obanpointer
Qantas - Qantas Frequent Flyer
Member since 08 Jun 2014
Total posts 318
Have booked in oz and Singapore. No issue. No cost. Just call them.