"It seems that at least in part his reasons for shifting to Queenstown were to escape from Mr Macdonald," French wrote.
Boe, who moved from Feilding to Queenstown in April 2010, was not implicated in Guy's killing.
However, police told the sentencing judge Boe's disclosures were "significant" to the murder investigation. "It is unlikely there would have been sufficient evidence to arrest Mr Macdonald without the assistance provided by Mr Boe."
Boe's lawyer Anne Stevens' appeal was partly on the grounds that not enough discount was given for "mitigating circumstances". She had submitted that without Macdonald, none of the crimes would have happened. The Crown had accepted that Macdonald was the "primary offender".
The starting point for Boe's sentence was four years.
He had received a 50 per cent discount for admitting his crimes to police.
But French granted him 60 per cent, which cut his term from 24 to 19 months.
Boe was brought up by his grandmother after his parents died when he was a child.
A psychiatric report presented at sentencing confirmed Boe was not suffering from any major mental illness but "tragic events in his childhood" had rendered him especially vulnerable to the influence of an older man such as Macdonald.
When arrested in Queenstown he had been completing a building apprenticeship and his employer and other referees wrote to the court in "glowing terms" expressing "amazement and shock" and said the offences were "totally out of character".
The pair pleaded guilty to stealing two stags from a Feilding farm in December 2006. After being caught poaching deer on Nigel Sexton's farm near Foxton Beach, they returned and destroyed $5000 of milk and used a hammer to kill 19 of a neighbour's calves - Boe killed nine - valued at $5700.
They also set fire to and destroyed a house on Guy and his wife Kylee's property, causing $650,000 damage and $13,500 worth of damage to the Guy's new Feilding home.
Macdonald left obscene graffiti and used a splitting axe to smash holes in the walls while Boe used his boots and elbows.
Finally, in March 2009, they burned down Sexton's historic duck-shooting whare.
Boe told police he would do anything to undo the "stupid things he had done in the past".
He also insisted that he would never come to their attention again.