It's very difficult to confirm whether a dog is a dingo or not in the field. The colour variation is not a reliable indicator. Skull size and the ear canal ( much larger on dingo) can help to identify them. National studies show that there is just about nothing on the Australian East Coast that is even approaching pure dingo. Even in hybrid dogs where there is less than 50% dingo purity they will still look like dingoes due to the dominance of the gene. I was involved in a study ( a fair percentage of my business is soft catch trapping) in the Cairns/ Aloomba basin a few years back with CSIRO which found a very low purity level up this way. Can't see Victorian dogs having higher purity given proximity to domestic dogs over the years.