The mastermind of a fake jewellery store robbery and a man he enlisted to take part in a failed $2.5 million insurance fraud bid have been hit with a combined jail sentence of over eight years.

'What do you think is going to happen?' Mounir Helou was heard saying over an audiovisual link from custody before being sentenced at Sydney's Downing Centre District Court on Thursday.

'I don't know my friend, I don't know. I'm so scared,' former jewellery store owner Michel Elias Germani replied.

The pair were part of a group that planned and performed the sham robbery of Germani Jewellers at Sydney's Hilton Hotel in January 2023.

Germani was the mastermind of the scheme while Helou and another man attended the store after hours.

They tied up the store owner and his shop assistant Lana Al-Khoury before making off with $20,000 in cash and $120,000 in jewellery, which they were promised as a reward.

Germani, 68, is incarcerated at Parklea prison while Helou, 60, is at Long Bay, both in Sydney.

They watched on Thursday as Judge Georgia Turner handed down their fates, over three years after the fake robbery.

The judge found Germani was $184,000 in rental arrears when he hatched the scheme as his landlords at Hilton looked to swoop in and take control of the store.

Germani had tried twice before to enlist someone for the sham robbery.

On the first occasion, those he hired took off with his money while the second individual he contacted got in touch with police instead.

Germani also increased his insurance limits weeks before robbing his own store.

Judge Turner said she could not find, on the balance of probabilities, that Ms Al-Khoury was in on the scheme herself.

Germani sought a discounted sentence after saying he offered to assist police to investigate or prosecute the shop assistant.

He claimed Ms Al-Khoury had agreed to the sham robbery if she received help making a workers' compensation claim.

However Justice Turner said there was no evidence these allegations were reliable or truthful or that police had actually moved to investigate.

Both Germani and Helou were sentenced over one count of attempting to dishonestly obtain a financial advantage by deception.

Germani also pleaded guilty to one count of perverting the course of justice over two police statements in which he lied about the robbery.

He claimed 164 items worth over $2.8 million were stolen.

The insurance company ultimately rejected his claim but not until after it spent almost $50,000 investigating it, the judge said.

Germani was handed a maximum sentence of four years and 10 months.

His non-parole period of three years and three months will expire on August 7, when he will first be eligible to walk free.

Helou was given a sentence of two years and 10 months for his role in the sham.

He will be released on July 10 after spending one year and seven months behind bars.

Both men had their sentences backdated to take into account time already served.

In April, after a jury retrial, the pair were found not guilty of aggravated robbery using corporal violence.

Jurors also found Germani not guilty of one count of kidnapping with intent to obtain an advantage.

Prosecutors unsuccessfully tried to prove that Ms Al-Khoury was an innocent victim of the scheme.

Born in Lebanon, Germani's father was a judge and his twin brother was abducted by Hezbollah.

He broke up with his second wife Coco Germani in 2025 because of stress caused by his incarceration.

At the time of the robbery, Helou was serving a jail sentence in the community after being convicted for supplying a prohibited drug, taking part in an enhanced indoor cultivation, and driving recklessly or dangerously.

Before the failed fraud came to light, Germani's website boasted it had designed jewellery for Princess Diana, Saudi and Jordanian royalty, and Elizabeth Taylor.