Was John Ainsworth Horrocks the Australian explorer shot by his own camel?

Yes. The first camels came to Australia for the purpose of aiding the exploration of John Horrocks. One of these camels shot Horrocks. This occurred when the rather bad-tempered beast named Harry lurched to one side while Horrocks was unloading his gun, causing the gun barrel to discharge, right through Horrock's hand and into his jaw. Horrocks died several weeks later from subsequent infection. Harry the camel was then shot.