The committee's final report, handed down on Thursday, recommended the influence of property developers in the Hills Shire region be referred to the Independent Commission Against Corruption.
It found Liberal party operative Christian Ellis and Jean-Claude Perrottet, brother of Premier Dominic Perrottet, sought $50,000 from a businessman for an operation to unseat the federal member for Mitchell, Alex Hawke.
The committee chair, Greens MP Sue Higginson, said efforts by them and others to avoid giving evidence before the committee were "unprecedented".
"Never has a committee been faced with such serious, deliberate and co-ordinated attempts to evade service of a summons," Ms Higginson said.
The committee was formed in December after state Liberal MP Ray Williams used parliamentary privilege to allege senior party members were paid to install developer-friendly councillors to The Hills Shire Council in Sydney.
Mr Ellis and his mother Virginia Ellis, a Hills councillor, were both summonsed to appear as witnesses to the inquiry but successfully avoided service by private process servers.
Another brother of the premier, Charles Perrottet, and property developer at the centre of the allegations, Jean Nassif, were found to have engaged in "serious and deliberate" attempts to avoid giving evidence to the inquiry.
Toplace employee Jeff Egan, as well as Jeremy Greenwood and Dylan Whitelaw, were also found to have deliberately avoided providing evidence.
The report recommended both Perrottet brothers, Mr Ellis and Mr Nassif be called to give evidence to another inquiry established by the next parliament.
It also recommended Local Government Minister Wendy Tuckerman consider placing the Hills Shire Council into administration.
During a final day of evidence on Thursday, the committee heard evidence deputy federal Liberal leader Sussan Ley was the target of a branch-stacking operation organised by a party powerbroker who wanted her seat.
Shirlee Burge, a councillor and Liberal Party member based in Deniliquin, told the inquiry she met Mr Ellis in late 2020 or early 2021 after branch members complained about an "unusual influx" of new members.
"We met for coffee, where he informed me he had political aspirations and wished to be the next federal member for Farrer," she said on Thursday.
Cr Burge said she suggested he follow around the local MP, Ms Ley, for 12 months to learn the ropes and get to know the electorate in the NSW Riverina region.
"He refused and said, and I quote, 'I want it now, I'm not waiting'," she told the inquiry.
"He was adamant that he didn't want that, he wanted to be straight away the federal member."
Jean-Claude Perrottet, 26, on Tuesday told the committee he was overseas and would not appear, while stating it was clear he would "never receive procedural fairness" at the inquiry.
"False" allegations against him had been politicised and calls for the public to report his whereabouts had compounded his stress and placed his fiancee and their families in harm's way, he said.
The letter was only published on Thursday after the committee initially doubted Jean-Claude authored it, minutes show.
Charles Perrottet, a resident of Victoria, last week raised concern over some committee members' "partisan, ill-informed, speculative and defamatory" commentary.
The committee recommended the NSW Legislative Council refer an inquiry into the Parliamentary Evidence Act 1901 to the Privileges Committee, with a view to identifying amendments that would deal with some of the challenges the committee experienced in summoning witnesses.
