His younger brother and co-worker, Mii, 17, watched in horror as Joshua fell backwards off the truck step, was crushed and pronounced dead at the scene by paramedics.
According to documents released to the Herald on Sunday under the Official Information Act, Alpha's operations manager, Marie Gibson, went to the home of driver Raymond Brown a week after the second death and asked him to sign and pre-date a "Health and Safety Reminders" notice.
A Department of Labour report stated Gibson was "already closely involved in the DoL/police investigations of the Willy Nicholas fatal accident".
Gibson asked Brown to sign and pre-date the form - which he refused to do. Gibson later told investigators she had been "distraught" after Joshua's death and had panicked. No actions were taken against her and she recently left the company, which has changed its name to Kiwicare Waste Services Ltd.
Alpha pleaded guilty to failing to take all practical steps to ensure the safety of Nicholas, and was ordered to pay $60,000 in reparation and fined $32,400 in March this year.
The Herald on Sunday can report on the case only after suppression orders were finally lifted by a coroner last week.
Driver Brown, 59, pleaded guilty to careless driving causing death and was given a two-month community detention sentence and disqualified from driving for six months.
Judge Gerard Winter said that at a hearing into Nicholas' death, he was assured Alpha had taken great care to improve safety practices.
"I see the responsibility for this matter being shared by you and by the people that employed you"' he told driver Raymond Brown in court.
"If they had put the reversing technology into place on these trucks then perhaps we would not be here today."
Joshua's mother, Moe Mai, said she still grieved for her son every day and photos of him adorned every wall of the living room of her Otara home.
"He might be gone but he is still in my heart. I can't let him go."
She said Mii was still traumatised by seeing the death. "Imagine seeing your own brother with that kind of accident. He doesn't talk about it but I always talk about Rob to him."
Court documents show that Alpha has improved reversing technology and drug-testing among workers.
But the father of Nicholas, also named Willy Nicholas, alleged there was a culture of drug-taking at the company, which was contracted to the Auckland Council to collect 70 tonnes of rubbish a year.
Nicholas said his son died while working what was known as a "freebie" shift - where casual workers volunteer in the hope that they will be given work the next day. "Willy should never have been working in the first place."
Joshua's death is the subject of an ongoing coroner's inquiry. Auckland Council refused to comment as the coroner's inquiry was ongoing.
ACC reported 76 workplace accidents at Alpha in 15 months.
In the year to June, there were 85 deaths and 445 serious non-fatal injuries in workplaces in New Zealand.
