The former acting deputy secretary of Victoria's planning department, Jim Gard'ner,??? told Fairfax Media that if he had known the 2013 meeting was a political event he would have sought advice from his department about whether it was appropriate to attend.

"It was my job (as a public servant) to attend meetings requested by the minister. Meetings of a political nature we would not normally attend," Mr Gard'ner said.

Under public service guidelines, bureaucrats are required to "avoid any participation in activities which support a political party, including attendance at fundraising events".

Mr Gard'ner's comments raise further questions about the appropriateness of the penthouse meeting and Mr Guy's fundraising activities in his time as planning minister in the Baillieu and Napthine governments.

Fairfax Media revealed on Tuesday that Liberal deputy leader David Hodgett's office accepted a $10,000 payment in return for the lunch with Mr Guy. An invoice for the lunch was then issued by Mr Hodgett's office, with the money paid into his local electorate account.

While the donation was described in an invoice as sponsorship of an "industry forum", Mr Hodgett did not invite any other planning or property industry figures to the event or promote the fundraiser.

Documents obtained by Fairfax Media reveal that lobbyist Stephen Kerr helped organise the penthouse meeting after his developer client sought to meet Mr Guy to discuss an inner city project.

An email sent to Mr Guy's office states that the meeting with Minister Guy and Jim Gard'ner was to examine options "for moving our development plans forward".

Mr Gard'ner told Fairfax Media that he recalled the penthouse meeting and that public servants attending meetings with developers and lobbyists was a means of enhancing probity and standards at the time.

However, he was not told the lunch was a fundraiser and public servants would "not normally attend" such meetings. He said there was a number of people present but he could not recall exactly who, nor whether only one project was discussed.

Mr Gard'ner said it was not his job to "assist attendees" at this or any other meeting, beyond giving factual advice. He said he had never felt compromised by any of the planning ministers he had worked for, Coalition or Labor, but that every minister had "their own style".

In the wake of Tuesday's revelations, a furious Mr Guy accused Fairfax Media of reporting "fake news", and defended his actions as entirely "above board".

"I didn't run the event. I turned up to the event. I turned up with a staffer. I turned up to one of them with a departmental official. Right, how many departmental officials turn up to government functions today? I guess the answer would be zero. None. Right? None. I had a level of probity back then that no-one has today," he said.

But while Mr Guy told radio station 3AW he had "no idea" if money was paid to organise the penthouse meeting with two developers, only hours later, Mr Hodgett contradicted him, telling journalists: "Matthew would have known it was a fundraising event."

Both men also insisted the penthouse event was similar to forums run by Labor's Progressive Business fundraising vehicle.

However in a statement to Fairfax Media, Progressive Business executive director Fleur Morales said the organisation "operates a set program of business forums, boardroom lunches and twilight briefings, normally involving between 15 and 100 members from across a wide range of industry sectors".

On Tuesday, Mr Hodgett told reporters that at the meeting "there was no discussion about a development going ahead". Pressed about whether future developments were discussed, he said: "Look, I don't know the content of that hour and a half discussion. These forums are not about [anyone saying] 'we would like this or we want this development'."

The revelations come as Mr Guy continues to combat internal leaks about his past behaviour. A Liberal source has told Fairfax Media that earlier this year, Mr Guy was so concerned he was being monitored, he paid an ex-policeman to sweep his house with a scanning device for secret listening devices.

Mr Guy's house was "swept for bugs" several weeks before the donations controversy surrounding his lobster dinner in April with an alleged mafia boss.

The Liberal party also used the same ex-police officer to sweep its headquarters for listening bugs after former state president, Damian Mantach, was accused of fraud in 2015.

The penthouse revelations came as Labor promised to reform donation laws in Victoria. Mr Guy has offered to work with Labor on donations reform announced by Premier Daniel Andrews on Monday, including a donations cap of $4000 over four years and real-time disclosure of donations.

He also promised his own donations reform if elected in 2018, modelled on Canada's tightly regulated campaign funding regime.