"It was the worst thing I could have ever done. He was abusive and he was sexually starved.
"It made me sick, it churned my bloody stomach up."
Ms Lenaghan said she went to court twice during Wilson's trial, and was disappointed with his 21 year prison sentence.
"He should have got a lot longer."
Colin McKay, a retired detective who led the investigation into Wilson, shared the concerns of the parole board, believing Wilson's lack of acceptance of his crimes made him a risk of reoffending.
"Personally I believe he should serve the 21 years, that is what he was sentenced to," he told Radio New Zealand.
Mr McKay said unless Wilson were to make threats or reoffend, there was little authorities could do to halt his release next year.
He said he took advantage of his victims' "vulnerability".
"He was a very manipulative man. He took advantage of all of these people when a lot of them were at a very low point in their lives."
The Parole Board yesterday released its latest review findings, saying he remained at a high risk of reoffending and he should remain in jail.
"Of significance for the board was Mr Wilson's reported response to an inquiry regarding his ability to adhere to a condition that he have no contact with any child under the age of 16 years,'' the board said.
"Mr Wilson is recorded as having stated: 'I don't give a stuff about it'.''
Wilson was allowed to cross examine a clinical psychologist, whose name was withheld, who had prepared a report for the board.
"Mr Wilson had carefully thought out his questions,'' the report said.
"They focused, to a significant extent, upon his contention that (the psychologist) has misrepresented or twisted comments made by him during the interview she conducted on 1 September, 2011.''
The psychologist found Wilson was four times more likely to reoffend than the average person, and had a higher probability of committing serious violent offences within two years of his release.
She did not consider his "advancing age'' mitigated these risks.
Wilson had started seeing an ACC-funded counsellor but undertaken no other intervention aimed at addressing his offending or managing his risk of reoffending.
"He is reported to not to have requested any engagement with a psychologist and that he has not developed a release plan with his case manager,'' the report said.
Wilson told the board he intended to go whitebaiting upon his release, and that he would be supported by a Catholic brother and the Prisoners Aid and Rehabilitation Trust.
However, he admitted he did not expect to be released.
"The parole assessment report notes Mr Wilson's continued denial of his offending; his lack of co-operation in relation to any appropriate treatment programme and his unwillingness to disclose for full consideration and approval any proposed accommodation or reintegration plan,'' the report said.
"In the board's view, the risk of Mr Wilson committing a specified offence before his applicable release date remains a real and substantial one and that, by an appreciable margin, it is greater than the risk of recidivism which ordinarily arises in relation to such offending.''