Constable Zachary Rolfe shot Kumanjayi Walker, 19, three times as he resisted arrest in Yuendumu, northwest of Alice Springs, on November 9, 2019.
The inquest examining the 31-year-old officer's actions in the lead-up to and during the shooting will resume on Monday.
Const Rolfe left Australia last week after he penned an open letter defending his behaviour.
His father told The Australian he was unsure if or when or his son would return.
Const Rolfe said the NT Police Force had wasted millions of dollars on disciplining him rather than giving him a medal.
"Despite this, the coronial focus is still on me rather than on areas that could improve the circumstances of the NT," he wrote.
Previously, he had refused to answer questions as part of the inquest.
He was in the midst of appealing a NT Supreme Court ruling that would compel him to answer uncomfortable questions at the inquest. The appeal was scheduled for April 11.
He was acquitted last March by a jury after a high-profile five-week trial.
The death and the trial ignited grief, anger and a strong sense of injustice in the community.
The inquest was established in early September to hear voices from his community, and to examine the wider circumstances surrounding the shooting.
The inquest has heard from more than 50 witnesses so far.
Experts have told the inquest Const Rolfe's decision to forcefully enter and militarily clear the house where they found the Warlpiri man was risky and against orders.
The coroner has also heard Const Rolfe sent and received racist, sexist and homophobic text messages during conversations with other officers, which he claims have been cherrypicked to paint him in a certain way.
Const Rolfe defended the terms used in these messages as playground language in the letter.
