LNP defector Ray Hopper has admitted he met with Katter's Australian Party late last year, but declined to join at the time because he "didn't want to".
The revelation, one he repeatedly denied when accusations were made late last year, coincided with a lashing from the KAP candidate who fought to win Mr Hopper's Condamine seat in the 2012 election.
Mr Hopper announced he would quit the LNP and join the KAP on the weekend, warning that others may follow suit.
Registered nurse John Mathison told APN Mr Hopper had approached the party in October and November last year, convincing the new party he would run as one of their candidates.
When Mr Hopper dropped out of the process to stay with the LNP, Mr Mathison was brought in as the new candidate.
The KAP won 21% of the vote, second only to the LNP's 58%.
"Ray suddenly announcing (he would join the KAP) does not mean he just woke up one morning and decided that," Mr Mathison said.
"I have no doubt he may have decided this before the election.
"Rather than go to the polls as a new KAP member, he could go in knowing he was going to win but switch down the track."
Mr Mathison described his former opponent as "intellectually impoverished and morally bankrupt".
Mr Hopper hit back at the insults, saying Mr Mathison just had sour grapes after being beaten.
When asked why not just join Katter's party before the election, he said, "Because I didn't want to then".
"That was a decision I made but (Premier Campbell) Newman, (Deputy Premier Jeff) Seeney and (Treasurer Tim) Nicholls have been a disaster.
"I'm happy with my decision."
Meanwhile in Brisbane on Monday morning, Education Minister John-Paul Langbroek said he hoped to see a vision of unity emerge from the cabinet and party room meetings to be held in the afternoon.
Unfortunately, what emerged instead was news that Brisbane member Carl Judge had been asked not to enter the party room
Deputy Premier Jeff Seeney told reporters he would be allowed in once he gives his public backing to the Premier.
Mr Hopper told APN it showed "the bullying and thuggery" that he was keen to leave behind.
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