It would mean Taimo would need to prove he was no longer a risk to the community and could be recalled to prison at any time for the remainder of his life.
However, the Court of Appeal dismissed the Crown's appeal today.
Justice Mark Woolford, Justice Mary Peters and Justice Forrie Miller said: "Although we have disagreed with [Justice Moore's] reasons in some respects, we are ultimately not persuaded that he was wrong to conclude that the sentence imposed will provide adequate protection for the community and so must be preferred over preventive detention."
The judges found there were other factors which justified Justice Moore's conclusion for the once well respected figure in Auckland's Samoan community, who is registered as a child sex offender and could be subjected to an extended supervision order on his release from prison.
"The respondent is now 56 and will be 78 on the sentence expiry date," the Court of Appeal's judgment reads.
"He does not enjoy good health, and in the nature of things his health will have deteriorated further by the time he is 78. In other cases where preventive detention has been imposed, the defendant would have only been in their 40s or 50s when the otherwise appropriate sentence of imprisonment had been served in full.
"Twenty-two years' imprisonment is a long sentence."
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In determining the sentence, Justice Moore used a combined starting point of 23 years' imprisonment which was reduced for personal factors of remorse, historical abuse suffered by Taimo and ill-health.
"You are not an old man in biological years but neither are you young. Your physical health is poor. You suffered a heart attack in 2014 and underwent a triple bypass," the judge said.
"Without doubt, you have completely destroyed any sense of trust you previously enjoyed within your community. I expect you will be totally and permanently ostracised."
Justice Moore also said Taimo's crimes were "unprecedented in this country" and called the sheer scale extraordinary.
At the appeal hearing, Walker said Justice Moore had "understated Mr Taimo's risk of reoffending and overstated his ability to rehabilitate".
She said Taimo's risk profile, paedophilia, emotional connection to children, and proximity to children upon release were all reasons for the state to potentially detain him for the rest of his life.
Taimo has been given the specific diagnosis of paedophilia.
A "disillusioned community deserves life-long protection from him", Walker added.
Taimo's lawyer Panama Le'au'anae has said the Parole Board would rightly act as Taimo's gatekeepers.
He said his client "can be categorised as the sexual predator of South Auckland" and has no community support other than some of his close family members.
There was also a "strong possibility" of an extended supervision order to help monitor Taimo upon his release from prison, Le'au'anae said.
During the trial, Taimo claimed his victims were lying.
"It was you [who] the jury determined was a liar," Justice Moore told Taimo at sentencing.
His offending first came to light when an aunt for one of the boys overheard him "talking to other children about what had happened".
Police were informed in 2016 and further victims were identified and came forward.
One victim said to Taimo at sentencing: "How can you call yourself a man of faith? And have the devil dictate your needs?"
One of the survivor's mothers also hoped Taimo would "rot in jail".
"I have never hated something or someone so much," she said.
Suppression orders prevent the Herald from naming any of the schools or sports clubs Taimo worked at during his offending.
