Let's get legal
I really don't know the laws in Australia, but my guess here is that work related injuries are treted differently from "normal" injuries. In respect of lost pay, etc.
In Spain you get about 85% ill-pay for a normal illness, and you don't get any money for the first two days. But if it is work related, you get 100% (as it should be), and you don't get the money from social security, but from the company mutual. And all "in itinere" injuries are considered work related, so if you get injured while travelling, it is a work injury.
Mu guess is that the laws in Australia are somewhat similar.. so yes, it is work related, as she was not at home on a work trip!!