A Gold Coast accountant and a business owner accused of involvement in a "boiler-room" fraud are no longer facing charges after a magistrate declined to proceed against them, citing a lack of evidence.

In September, the Commonwealth brought charges of dealing with the proceeds of crime against Anthony John Restaino, 43 and Graeme Dwyer, 67, as part of a major fraud investigation involving the Queensland Crime and Corruption Commission (CCC) and Queensland Police, called Lima Violin II.

The charges replaced an initial one of money laundering. But a magistrate in Southport determined not to commit either man to trial earlier this month, finding there was insufficient evidence.

According to the CCC, 10 people remain before the court on a combination of various fraud and money laundering offences as a result of Lima Violin II.

The two-year operation focused on the activities of a private investigations company Phoenix Global, and its owner, former Queensland police detective Mick Featherstone.

It was sparked after police stumbled on links to Phoenix Global during an investigation into alleged fraud involving the Black Uhlans and Bandidos outlaw bikie clubs.

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In February, Featherstone, his wife Zoei Keong and his son Zach were given bail after being charged with fraud over alleged scams totalling up to $20 million and involving up to 600 victims.

Mick Featherstone has appeared in court over the alleged fraud. ( ABC News: Alyse Edwards )

In September 2014 the ABC revealed that the private investigator and three Gold Coast-based companies linked to him were under investigation for running boiler rooms that promoted investment schemes based on sports betting.

High-pressure sales offices would allegedly cold-call people around Australia, promising them high returns if they invested in the schemes.

Hundreds of people bought in, with some spending tens or even hundreds of thousands of dollars.

In May last year, the then-head of the CCC, told the ABC the crime watchdog was investigating the possible corrupt involvement of former police officers in protecting boiler-room scams.

But the CCC has since said there would be no further arrests of former officers following the charges against Featherstone.