Shall I organise the lynch mob? I appreciate that you see far too much unnecessary slaying of snakes Rob but until we know the full circumstances one really cannot jump to conclusions.
There is one very clear puncture mark and a few other likelies. The kinked back is typical of the breaks in the backbone that result from a snake being violently shaken in a dog’s mouth. There is also a straight edged wound with no apparent fluid having issued from it as there are no sand grains sticking to this area, as there are in other areas. So if you asked me to guess what had happened, I’d guess that the dog took to the snake and the owner, after becoming aware of what was happening, got the dog away. As the snake was still moving, probably nerve twitches that occur after death, the owner has attempted to ‘put it out of it’s misery’ using a not-too-sharp straight edged object, probably only to find that did not make any difference. But, that is all hypothetical. Whether it is correct or not, it adds no worth to this thread. I would add that anyone who has seen an ID thread on APS where the OP has admitted to either killing a snake or finishing the job, is very likely to be extremely reluctant to reveal any details of how a snake met its end on their property.
What seems to have been neglected is to state the obvious. The scales on the snake have raised ridges running along the middle of each scale. These are called keeled. While some Death Adders have keeled scales they have short and very squat bodies with very a non-tapering tail and a large triangular head. That leaves only two possible candidates for your snake, the Keelback (Trop mairii) and the Rough-scaled Snake (Tropodechis carinatus). The former, as stated, is non-venomous and entirely harmless. The latter is dangerously venomous. To the untrained they look alike and would readily be confused. Given that field IDs often involve moving snakes, this only adds to the confusion. Unless you are certain, it is better to assume that a snake make be dangerously venomous. Do not make the mistake that small snake are not as dangerous because there are quite a few dangerously venomous snake’s whose young can deliver a lethal bite at 20-30 cm.
So what to do? Watch the snake at a safe distance e.g. 3m and phone for a snake relocator. Keep continuous eye contact with it until the relocator can arrive. If you have kids or pets, get rid of all snake hiding places around the dwelling – grass short, nothing loose sitting on the ground, rockeries sealed with concrete between rocks, bottom of all bushy shrubs trimmed well above ground. Under these conditions, any snake will be a transient visitor.
A significant percentage of fatal snake bites result from individuals attempting to kill snakes. Yet snakes would rather avoid an encounter with humans if given the choice. Australian snakes are not aggressive but they will defend themselves if attacked or cornered, like most animals. There is a very simple rule when it comes to snakes.... if you leave them alone, they will leave you alone!
Blue
PS. I concur that the presence of a loreal scale can be distinguished. The upper labials are dark-edged, a characteristic of Keelbacks but not the RS. Both eyes are visible as the sides of the head of a Keelback slope inwards versus vertical in the RS. The most obvious feature is the diagonal ‘checker-board’ patterning of the dark scales whereas in the RS they are always in a transverse band even if not contiguous.