The 56-year-old was shot dead in a hail of bullets by Victoria Police Special Operations Group members on the remote property in Thologolong, near Walwa on the Victoria-NSW border, on Monday after a seven-month manhunt.
Sources not authorised to speak publicly about the case confirmed police had received a tip from a member of the public that led to Freeman's location.
Victoria Police Chief Commissioner Mike Bush was tight-lipped on Monday on whether the $1 million bounty for information leading to Freeman's capture would be paid.
Any claim of the reward would likely remain confidential indefinitely, Mr Bush said.
But a source told AAP on Wednesday the reward was being claimed.
Speculation about how Freeman came to be in Thologolong has been rife, although Neil Sutherland insisted his brother, who owns the property where Freeman was found, had no idea.
He said his brother had been in Tasmania at the time and, unlike Freeman, was not a sovereign citizen.
Mr Sutherland, who lives two properties from the site of the shooting, has reportedly said his brother has contacted police to offer his assistance.
Freeman's body was formally identified on Wednesday, days after the shooting.
Police confirmed homicide squad detectives were leading the investigation.
A recent fire in the Walwa-Mt Lawson State Park, sparked by a lightning strike near where Freeman was found, will also form part of police inquiries, investigators said.
As one of the nation's largest searches concludes, a coroner will take over the investigation and look into the circumstances surrounding Freeman's seven months in hiding.
Freeman was wanted over the fatal shootings of Neal Thompson and Vadim de Waart-Hottart, who were among a team of officers serving a warrant at his Porepunkah home in late August.
The coroner will examine all three deaths in detail to establish who died, how they died and what could be done to prevent future deaths, Queensland University of Technology forensic criminologist Claire Ferguson said.
As part of that process, a brief of evidence will be compiled, witnesses will be called and the judicial official will also study the final moments of Freeman's life and the police decision to shoot him.
"They'll have a full reconstruction of what actually occurred and that might be establishing people's exact positioning in the scene and forensic evidence," Dr Ferguson told AAP.
The highly technical 3D reconstruction would be aided by statements from those who shot Freeman, what he was doing, what he looked like, what firearms he had and the decision-making process around shooting him.
Minute details, including the trajectory of how he was shot and the specific aid rendered after the fact, will also be described to give the coroner a sense of what was happening at the scene.
Footage showed Freeman wrapped in a blanket when he emerged from the shipping container, which appeared to be part of a makeshift campsite, before pulling out a gun and pointing it at police.
It is not known if he fired the gun before multiple officers discharged their weapons.
Whether that video will ever see the light of day will depend on the coroner weighing up the benefits of transparency and accountability and the probative value of people seeing police shooting someone, Bond University criminologist Terry Goldsworthy said.
"It's not beyond the realm for the coroner to think this footage will show police did all they could and to make sure that there's no conspiracy theories that Freeman was unlawfully shot," he said.
Child-sexual abuse allegations levelled against Freeman will be investigated to inform the coroner on the police's initial decision to attend his property, but a finding of guilt would not be made, Dr Goldsworthy said.
The coronial process will give the police officers' families and Freeman's family a clear outline of what occurred.
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