> The stewardship claim bit seems maybe a bit overstated considering they weren't able to secure an object the size of a button leading to it "falling off the back of a truck"

As I understand it, this wasn't fuel, it was part of an instrument used by a mining company to measure the density of iron ore. The mining company (or a contractor depending on what you read) are the ones that lost it, the Australian government agency just came in to help find it.