I understand your perspective. However, to me, the harvesting of living beings for meat is a too-convenient excuse to justify a quick solution and cruelty; moreover, it discourages more creative and better, long-range solutions. Death is not a purpose.
Perhaps I don't understand the logistics of the situation but if the indigenous people are in a dangerous location for water, with the fires and all, wouldn't it be wiser to relocate them - at least temporarily - til the problem has been brought under control (or if it cannot be, won't they need to be moved anyway)? The camels could also be relocated (and darted with birth control).
The visual is, a billion animals have already lost their lives, and now Australia wants to kill more. No matter the reason, this doesn't sound or look good.