As an outsider, I've been wondering when someone would point out that Sunnyfield was then sub-contracted to do the work.
Qantas must follow a strictly commercial policy, agreed. It's not a charity.
On a strictly commercial level there is ony one possible conclusion. Whoever was responsible for this tender process was incompetent or corrupt, perhaps both.
What's the evidence for that? That the work was sub-contracted to Sunnyfield, presumably with the Corrections Department taking a slice. As always when something like this happens, the next question is which individual(s) have suddenly got some extra spending money. As we in the old world say, "Cui bono?"