Royal commission is urged to make a finding that regular cash payments from a Sydney underworld figure has links to a NSW union official.
And two Queensland officials from the Construction, Forestry, Mining and Energy Union may face charges over the alleged destruction of evidence, with lawyers assisting the commission urging Commissioner Dyson Heydon to make adverse findings over the removal and destruction of tonnes of documents from the CFMEU's Queensland office.
Lawyers assisting the commission have recommended a finding that NSW CFMEU organiser Darren Greenfield received regular payments of $2500 from George Alex.
Mr Alex has been described to the commission as an undischarged bankrupt and a person with "well-publicised connections with organised crime".
Commissioner Heydon has been urged to rule that both Mr Alex and Mr Greenfield may have breached corruption provisions of the NSW Crimes Act.
Senior counsel assisting the commission say explanations by Mr Greenfield and Mr Alex of "incriminating" text messages were "not credible" and have recommended a finding that Mr Greenfield was induced to give favourable treatment to labour hire companies linked to Mr Alex.
A number of text messages, from Mr Alex to various people, tendered to the commission earlier this year, referred to money being left under a toilet sink at his Burwood home.
Commission lawyers said a 2013 message to Mr Greenfield that said "toilet first draw (sic)" should be seen as Mr Alex arranging a payment.
The commission's lawyers also found there is insufficient evidence to make a finding that NSW CFMEU secretary Brian Parker received corrupt payments from Mr Alex.
Commission lawyers have also recommended a finding that criminal charges be considered against Queensland CFMEU secretary Michael Ravbar and former union state president David Hanna over the removal and destruction of tonnes of union documents.
The material was disposed of in April last year, on the same day the CFMEU was served with a notice from the commission to produce evidence.
"The commission should find that Mr Ravbar and Mr Hanna's conduct was done with an intention to conceal the removal and destruction of documents," the submission to Commissioner Heydon said.
When Mr Ravbar and Mr Hanna fronted the commission last month, they blamed each other for trying to cover up the destruction of the material.
Both said it was the other's idea to cover security cameras during a massive but "normal" clean-out of the CFMEU's Brisbane office on the day it was served with the notice to produce.
The commission heard almost seven tonnes of boxes were taken to the dump in a hired truck.
The CFMEU dismissed the recommendations on Mr Ravbar as nothing more than "the view of the prosecution".
"They are not the findings of the commission," the union said in a statement.
"It's very important that it not be characterised as a finding."
CFMEU national construction division secretary Dave Noonan said the union stood by Mr Ravbar.
"We believe the chances of a successful prosecution, based on what we've seen, are so remote as to be ridiculous," he said.