The Cayman Islands registered firm Kreab Gavin Anderson went into voluntary administration on December 23, owing several former staff about $1.8 million wages, super and leave entitlements.

Administrator PKF has been appointed to deal with the case.

One of the former agency's office managers Nicole Miller told Fairfax Media they staff still have not been paid their superannuation entitlements. She says she is owed more than $6000 in superannuation.

Her written submission to the inquiry details her frustration. "I asked to the point of haranguing for my entitlements to be paid, however, they were ignored," the submission says.

Miller who worked at the firm between April 2015 and October 2016, made a complaint to Australian Taxation Office in mid 2015 which resulted in about $1200 worth of super being paid to her. But despite the initial slap on the wrist from the ATO, the firm later continued underpaying staff.

She says other staff who are also owed money had also made complaints, but the ATO has not told staff of how it plans to recover the outstanding money owed.

The submission says the former managing partner [Michael Morgan] and chief financial controller [Blayne Northcote] have not been compelled to explain why they deliberately did not pay staff superannuation.

"I say deliberately, because the non-payment of superannuation was an issue regularly raised by staff in office meetings," Ms Miller said in her written statement. "[They] regularly ignored calls and emails from staff."

"What I find most disappointing in this saga is not the non-payment of superannuation per se, but the way Kreab Australia was allowed to get away with non-payment and how still no one has been held to account for this illegal act."

She hopes the inquiry will lead to more stringent monitoring and enforcement of compulsory superannuation payments.

Mr Morgan told Fairfax Media: "Now that the company is in liquidation and its assets have been realised, any outstanding entitlements will be paid to employees by the administrators as a priority. This has been communicated to former staff by the administrators."

Mr Northcote declined to comment.

Employers are by law required to pay the 9.5 per cent Superannuation Guarantee (SG) to any employee that earns over $450 a month.

But as various submissions to a Senate inquiry into non-payment of the SG have noted, there's no visibility when superannuation isn't paid. Employee payslips must only state amount due, not the amount paid.

The Australian arm of Swedish consultancy Kreab merged with New York's Gavin Anderson & Co in 2009.

It was under the management of Michael Morgan, a former Labor Party senior official, who worked on a number of high-profile campaigns including the 2007 "Kevin07" federal election campaign.

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