The link in the post title (https://chuffed.org/project/dpk4nvzkr4emIf) returns "page not found" for me. The link in the YouTube video's text block (https://chuffed.org/project/dpk4nvzkr4em) works.

About the guy being tried - my personal opinion is that his goal was not to expose war crimes. He caused the war crimes investigation by a lucky accident. I hope he gets away with a mild sentence. For those who don't watch videos without absolute need:

https://en.wikipedia.org/wiki/David_McBride_(whistleblower)

https://www.smh.com.au/politics/federal/what-i-ve-done-makes-sense-to-me-the-complicated-colourful-life-of-david-mcbride-20190621-p5204h.html

Short summary: he was accused of leaking the documents. He pleaded guilty and will be sentenced in the coming May. Interestingly, he leaked the documents because he was dissatisfied with the excessive investigation of soldiers while journalists who examined his materials arrived at the conclusion that soldiers were likely committing war crimes and needed far more investigation. From Wikipedia:

Over two deployments to Afghanistan in 2011 and 2013, he became convinced the war was so dictated by political imperatives in Canberra - especially the desire to avoid civilian casualties - that it became impossible for Australian soldiers to do their jobs.

At the centre of his complaint lies a 2013 Defence directive to Australian soldiers stating they needed a high degree of confidence that anyone they fired upon was "directly participating in hostilities". If not, a soldier could be "exposed to criminal and disciplinary liability, including potentially the war crime of murder", according to the ABC's reports on the documents McBride leaked.

McBride argues this change increased the scrutiny of special forces missions. The hazard of possible murder investigations left the Australians hamstrung. "If you are that worried about Afghan deaths, why not pull us out?" he asks. "If you want us to fight the war, you have to be able to let us do it."

As for the war crimes (journalistic account)...

https://en.wikipedia.org/wiki/Afghan_Files_(Australia)

The documents contained at least 10 accounts of possibly unlawful killings of unarmed men and children.[2] Two of the incidents, both occurring in September 2013, are currently under investigation by the Inspector General of the Australian Defence Force.[7][2] These incidents involved the death of a man named Bismillah Azadi and his son Sadiqullah in an Australian raid in Uruzgan Province, when Bismillah allegedly pointed a pistol at SAS troopers. Contrary to the soldier's reports, police found Bismillah and Sadiqullah in bed beside each other the next day, apparently killed while asleep.[7] The documents also contained a report of a detainee alone with a soldier being shot after allegedly trying to seize a weapon.[2] Later in 2013 after these incidents, Australian troops allegedly killed an Afghan motorcyclist, and injured his female passenger. This incident allegedly sparked agitation from the Afghan authorities, who threatened to stop working with Australia unless the killing of unarmed civilians ceased.[2]

/.../

The files provided insight into the response of the ADF over, and background of an incident in which an SAS soldier severed the hands of an Afghan insurgent for identification confirmation purposes.[8] /.../ Mutilation of the dead, however, is a violation of the laws of war.

As for the investigation of journalists (not war crimes)...

On 5 June 2019, the Australian Federal Police raided the Sydney based headquarters of the ABC over a period of eight hours,[4] reportedly over the Afghan Files.[14] /.../ Following the raid the ABC began litigation against the AFP, claiming the warrant was too broad and thus not enforceable.[17][18] /.../ In February 2020 the case was dismissed by the federal court,[19] and the AFP began the process of accessing the confiscated files while the ABC rushed to get an injunction.[20][21]

In June 2020, the AFP sent a brief of evidence to the Commonwealth Director of Public Prosecutions (CDPP), the federal public prosecutor, recommending charges be laid against journalist Dan Oakes for breaking the Afghan Files story. As it was such a high profile case, prosecution also required final approval from the then Attorney General of Australia, Christian Porter.[22] In October 2020, the CDPP announced that, despite believing they would succeed in conviction on several charges, they would not be prosecuting Oakes.[23]

(I guess they understood that they would piss off the public with their witch-hunt against journalists. That left the leaker himself.)

As for the investigation of war crimes (military account)...

https://en.wikipedia.org/wiki/Brereton_Report

The report found evidence of the practice of "throwdowns", where Australian troops would carry weapons and equipment not issued by the ADF for the purposes of planting on civilians killed in combat.[14][10]: 29  The weapons were then used in photographic and other evidence to give the illusion that the civilians were legitimate combatants.[10]: 29  The report speculates that throwdowns started for the "less egregious though still dishonest" purpose of avoiding scrutiny when legitimate combatants were later found to not be armed, but later evolved into the concealment of intentional unlawful murders.[10]: 29 

The inquiry found that junior soldiers were often required by their superiors to murder prisoners to get their first kill, a practice known as "blooding".[15][5] Brereton described the practice as such: "Typically, the patrol commander would take a person under control and the junior member [...] would then be directed to kill the person under control".[16][10]: 29  Throwdowns were then placed and a cover story created to conceal the practice.[7] The killing of passive prisoners of war is a war crime.[17][18][19]

The report discusses at length the parties responsible for the criminal acts alleged, concluding that while senior commanders "must bear some responsibility",[10]: 30  "it was at the patrol commander level that the criminal behaviour was conceived, committed, continued, and concealed, and overwhelmingly at that level that responsibility resides."[10]: 33  The patrol commanders were corporals and sergeants, and the inquiry "found no evidence that there was knowledge of, or reckless indifference to, the commission of war crimes"[10]: 31  on the part of commanding officers from the troop/platoon level upward.[10]: 30–31 

...as for the results...

In response to the report, 2 Squadron, Special Air Service Regiment, was disbanded (with a new squadron to be raised at a later date),[25] and the Morrison government established a new Office of the Special Investigator to investigate further criminal conduct and recommend prosecution of individuals involved.[26][27][28] In December 2020, Home Affairs Minister Peter Dutton appointed a former Judge of the Supreme Court of Victoria, Mark Weinberg, as the Special Investigator.[29]

/.../

In 2023, the former Australian SAS soldier Oliver Schulz was arrested and charged with murdering an unarmed Afghan civilian. He is the first person to be charged in connection with the report. He is also the first Australian soldier to ever be charged under Australian law with a war crime.[38]