A tracking device was removed or fell off Borce Ristevski's car, which was fitted by police after his New Zealand-born wife Karen went missing.
Ristevski's badly decomposed body was found wedged between two logs on a property in Mount Macedon, about 60km northwest of Melbourne, on Monday, news.com.au reported.
Since the grisly discovery, Mr Ristevski's lawyer Rob Stary acknowledged the husband was the No 1 suspect. Ristevski denies any involvement, reportedly telling family members she may have been snatched by a stranger.
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• Borce Ristevski's lawyer concedes he is 'number one suspect' in wife Karen's murder
Fairfax Media in Australia reports the device was fitted to the car in the months after Ms Ristevski disappeared from the couple's $1.1 million home in Avondale Heights, in Melbourne's northwest, in June last year.
An autopsy on Ristevski's body has not found any signs of injury.
Defence lawyer Bernie Balmer told Fairfax Media establishing a cause of death would be crucial to the investigation.
"It's a process of elimination," he said.
"In order to charge and prosecute someone you've got to eliminate all other possibilities - that is wasn't an accident.
"It's crucial to find a cause of death."
Mystery around the case continues to mount as more people with information come forward.
The Herald Sun has revealed Mr Ristevski's brother, Vasko, had a connection to the area where Ristevski's body was discarded.
The former trainer of a racehorse owned by Vasko has a trainer's stud at Toolern Vale, about 20km from where the body was found.
There were also reports two men who allegedly looked like Mr Ristevski and his brother were bogged in a truck about 200m from where the body was found.
Macedon resident Dean told the Herald Sun he thought the men were from Serbia, Macedonia or the Balkans as they had an accent.
"I thought it was rather strange ... you'd go down there in a 4WD, you wouldn't go down there in a car and you certainly wouldn't go down in a truck.
"I had a conversation with one of them. (He) had that half-shaved, goatee sort of look."
Dean said he wondered if his sighting was connected to Ms Ristevski's case and contacted Crime Stoppers in August, two months after the Melbourne mother disappeared.
"I was absolutely convinced that what I saw was unusual and could be related to Karen Ristevski," Dean said.
He also said he saw bags of concrete and lime. However, there is no evidence that Borce or Vasko Ristevski were involved in Karen's death.
reported news photographer Jay Town was in the bush in July, a month after the mother went missing, when he stumbled across bottles of industrial strength fertiliser. He has spoken to detectives.
The trainer's stud reportedly linked to Vasko, is on Blackhill Road and borders properties that were being investigated by police during a search in December.
Locals reported Vasko was also hanging around an abandoned restaurant, near his former horse trainer's stud, after Ms Ristevski went missing.
The Australian reports he allegedly claimed a psychic told him to visit the restaurant, which burnt down about three years ago.
It is believed Vasko told family members that was the reason he was at the restaurant, after locals claimed to see him there a number of different times.
The Australian reports police searched the restaurant in October.
"He goes to see a psychic quite a bit," a family member told The Australian.
Vasko spoke out right after the disappearance and suggested Ms Ristevski fled the country on a fake passport because she was embarrassed by her stepson Anthony Rickard - Mr Ristevski's son - who was spreading rumours he was having an inappropriate relationship with the missing woman.
Anthony Rickard has admitted to having an ice addiction and Australia's A Current Affair programme claimed he tried to sell the programme his story.
Since the discovery of Ms Ristevski's body, another man, Gary Salt, told police he saw a man emerge from the forest at Mount Macedon, where the body was found, with a shovel.
He said he drove friends home after a party around November last year when his car lights panned over a man wearing a beanie and carrying a shovel.
Salt joked "what did you do with the body?" but was met with an expressionless face, according to the Herald Sun.
Victoria Police chief commissioner Graham Ashton said on Thursday: "It's one of the aspects being looked at but gee, it's getting a lot of speculation".
This week police also seized a shovel from the Ristevski home to test soil to see if it matches samples taken from the burial area.
Mr Ristevski claimed he had a fight with his wife about money the day she went missing. He said she left the home to clear her head but never returned.
Their 21-year-old daughter, Sarah Ristevski, grew worried and texted her mother's friends to see if they'd seen her. Fears increased when Ms Ristevski did not show up to work at her fashion boutique, Bella Bleu.