Coulter, who in his pre-sentence report had stated he was a "loyal friend" to O'Rourke, was sentenced to three years prison and was to pay the same reparation as his friend.
The pair, along with six other alleged accomplices, sought Mr Maynard after a drug deal in Queenstown had them left feeling "ripped off".
Mr Maynard was put into a car by the two after being kicked, punched, head-butted and had a meat cleaver held to his throat by Mr O'Rourke.
He was then taken to Arrowtown and dumped on the side of the road.
Some of the men had worn balaclava disguises during the assault and had burned some of the clothes they had worn on returning to Frankton.
Last month Samuel Coupe (28) was sentenced to two years, nine months in prison, Jonathan Burke to two years, three months and Daniel Kissell to eight months' home detention on charges of intending to commit a crime, namely theft by violent means, and wounding Mr Maynard.
This morning's sentencing took an hour and a half in front of a packed Queenstown District court room.