just some speculation........
It is possible the new boyfriend of Hazel ( the Carer ) dumped that suitcase at Wynarka. ... to set the scene..
it is odd, that Khandles body was hidden for so long, then so suddenly and ( you would have to say ) deliberately, bought into the open along the side of a well travelled highway.. as if suddenly, someone just had to get rid of it.. perhaps this someone only found out about what was in the suitcase in the shed.. someone who wanted rid of anything Daniel around his 'wife'.. looking at him today, he looks nutty enough....
My daughters theory is, Hazel, in a tender moment of sexual bonding , tells the 'Carer' about the body in the suitcase.. ( leaving out her part in the fraud element) and he goes completely bonkers and in his own eyes, 'gets rid of it'... quickly, cackhandedly, clumsily, and returns to Hazel having passed some sort of initiation into her inner embraces.. besides..... the temperature in Adelaide was nearly 30 celcius today, and what does the nutso 'Carer' have on? a thick woollen dufflecoat.
He is as nuts as the other two, or more..