That's only part of the equation.
I also heard numerous times that their Kruisers do not accept a WD hitch. WD hitches expect/require the tongue to be designed a certain way - I believe the A-frame needs to be at around 30 degrees, which may or may not be the case for Kimberley. Then there is the question of having physical room to attach it. Then the question of whether the frame is strong enough for the forces that will be exerted in that (attachment) spot. For example, some aluminum-framed trailers, like those from InTech, are showing up on classifieds with plates welded-on right where the WD hitch would connect; clearly a reinforcement (one that wasn't present in the original design a few years ago)... I wonder why.
Lastly there is the question of actual use. In the US you've got some highways with 80mph limits, and people towing at those speeds, passing (or being passed by) semis, etc. How common is that speed/environment in Australia? Perhaps the Australian market simply doesn't "need" WD hitches as much as the US market, so the trailers weren't designed for them.
On the same note, the European trailers are very different from what we get here, too. Look at the axle placement relative to whole trailer, look at the resulting differences in tongue weight, trailer stability (or lack there of) at speed, etc.
Different trailer markets pose different challenges and have their own, unique details. Worth thinking about in depth before simply importing a trailer from across the world.