Three of the complainants approached National Party deputy leader Paula Bennett, who said they felt fearful, intimidated, and not taken seriously.
"They've have been told to keep quiet about what's going on, that it should be kept as an internal process, advised not to go to the police. They feel they are losing all options and actually losing hope," Bennett said last week.
Labour's ruling New Zealand council met at the weekend, and Haworth released the council's decision in a statement this evening.
"Ensuring the appeal is done by an independent expert who is at arm's length from the party is important for building trust in the process in the future," Haworth said.
"Reasonable financial support will be provided to any person participating in the appeal process to ensure that they are able to obtain appropriate legal advice as the process proceeds.
"Personal and emotional support, independent of the party, will also be provided to any person participating in the appeal process."
He said there were a number of young people involved in the complaints.
"Ensuring their wellbeing is looked after is at the forefront of our approach."
Speaking at her post-Cabinet press conference on Monday, Ardern said that a neutral independent body should be brought in to investigate complaints to the Labour Party in some cases.
"There will be occasion where, given the nature of our organisation, it won't be possible, nor desirable for some complaints to be dealt with entirely in house, and having neutral parties able to help the party navigate complaints will be appropriate."
She said there would need to be a threshold before complaints would be investigated by the independent body, which would need to have the confidence of the party and the complainants.
"The nature of complaints that a political party can receive can be many and varied, but there will absolutely be cases where I think that will be necessary."
Haworth said details of the new process will be worked out at the council's next meeting.
Bennett said Ardern's comments seemed like a step forward.
"They felt intimidation and bullying, that the alleged perpetrator was too valuable and had senior MPs protecting him, so this sounds like a step forward," Bennett told the Herald.
But she said she was giving cautious approval as she did not know the detail of the proposal.
The current allegations followed ones of sexual harassment in February last year following a Young Labour summer camp.
A 20-year-old man was charged with four counts of indecent assault at the Waihi camp.
Ardern said last week that the current review was a test to see what the party had learned.
"The party's taking a good look as to whether or not we're satisfied with the natural process of justice and whether or not we've supported the complainants as we should have."
