A lot more than '30' truck drivers would be required even with...

A lot more than '30' truck drivers would be required even with so-called fake 'road trains', because an 1800 metre maximum length intermodal train from Parkes NSW (not Sydney) or Adelaide (not Melbourne) can be double stacked and may convey up to 220 12.2 metre (40') double size containers.

Here is a video of such trains: see 12:10 in the video (double stacking is not possible Parkes to Sydney/Brisbane or Adelaide to Melbourne due to tunnels, pedestrian and road overbridges and other structure lack of clearance).

Some trains are not double stacked across the desert, principally if their timetables minimise or eliminate shunting of new loading on in Parkes or Adelaide if the train say originated in Sydney or Melbourne respectively: