She will remain as MP for Papakura and is set to stand in the general election.
Further emails, expected to be released today, are believed to show Graham - who was at one time employed by Hotchin - and another right-wing blogger, Cathy Odgers, alias Cactus Kate, were behind attacks on Feeley.
Read more of our coverage:
• I'm the victim of a smear campaign: Judith Collins resigns
• Resignation reaction: 'Too little, too late'
• The email that brought down Judith Collins
• Collins resigns: Blogger backs mate
• Collins resigns: Jared Savage and Fran O'Sullivan respond
As former managing director of Hanover Finance, Hotchin was at the time under investigation from the SFO and FMA for his role in the failure of Hanover in 2008.
About 16,000 people with investments totalling more than $500million lost most of their money following the failure of Hanover and related companies and the sale of assets to Allied Farmers.
Correspondence obtained by hackers who targeted the Whaleoil site showed Slater and Odgers were working together with Graham to attack Feeley while he was responsible for investigating Hanover Finance.
The email released yesterday set out plans to discredit Feeley and was sent to a "Mark".
Several sources claim that was Hotchin.
It was also sent to a "Carrick" - Carrick Graham who was representing Hotchin at the time.
Collins denied any knowledge of the smear campaign, instead claiming she had been the victim, but was forced to resign after a series of controversies just three weeks out from the general election.
Slater wrote a series of highly critical blogs about Feeley in late 2011.
They covered allegations that could have damaged Feeley's reputation in the eyes of the public.
On October 7, 2011, he wrote a series of blogs titled "Staff Issues at the SFO".
One had claimed 23 staff had left the department at that time during his tenure.
Slater had written: "What sort of cowboy culture has been bred by Five Fingers Feeley at the Serious Fraud Office?"
It is understood emails to be released will show pressure was exerted on the SFO and the FMA to close their investigations into Hanover.
Odgers was a figure in the Dirty Politics book and last week her Hong Kong-based employer Jeeves Group confirmed she was no longer a consultant for them "by mutual consent".
It is understood that decision was linked to emails being released by the hacker today, which are expected to show the bloggers were being paid to discredit Feeley.
Slater says he "embellished" references to Collins in the damning leaked email that led to her resignation as a minister.
Last night Slater revealed he would lay a complaint with the Privacy Commissioner over Prime Minister John Key releasing the email that led to Collins' resignation.
He claimed Key had "breached my privacy", a charge he also aimed at Dirty Politics' author Nicky Hager.
Graham said he would not comment.
"I don't discuss who my clients are or the work I do for them. Facilitate is a private company and that's all there is to it."
In a statement last night State Services Commissioner Iain Rennie said he was "extremely concerned" at the suggestion that Collins had undermined Feeley.
"It is important that chief executives and ministers mutually support each other to carry out their respective roles.
"I am therefore extremely concerned by an allegation that a minister has associated with third parties to discuss influencing my assessment of a Public Service chief executive. If true, this would be wholly unacceptable."