Homicide investigators stopped Le Nghia Andy Pham, 26, at Sydney Airport on Sunday as he was trying to fly to Vietnam, and charged him with the March 2 murder of Taha Sabbagh.
Mr Sabbagh, a 40-year-old father, was shot multiple times in the chest while sitting in a car with his son in what police described as a callous, gangland-style killing.
Police allege the Fairfield East man did not fire the gun but played an integral role in planning and co-ordination before and after the execution, in Sefton.
He allegedly placed a second getaway car in position a week before the murder and, on the day of Mr Sabbagh's execution, helped ferry the alleged shooters to and from locations.
Pham remained in custody at Surry Hills Police Station on Monday when his lawyer Annabel Wurth did not apply for bail during a short mention at Downing Centre Local Court.
Bail for formally refused by Magistrate Greg Grogin, who ruled Pham would remain in custody for another eight weeks.
Pham has not entered a plea.
"He bought a ticket to go to Vietnam, what he got was a free trip to the police station, and hopefully he'll get the 'Go to Jail' card," Homicide Squad Commander Danny Doherty told reporters on Monday.
"What we're saying from all his actions, and multiple of them, he was completely complicit.
"The old saying, 'In for a penny, in for a pound'. Well, now he's been placed before the court on a murder charge which we believe is a strong case against him."
Pham allegedly applied for a passport after the murder and was intercepted on Sunday after investigators feared he would flee the jurisdiction.
Detectives have kept an open mind about the motive for killing Mr Sabbagh. One theory is that an organised crime network hired someone to kill him after a conflict.
Mr Sabbagh was shot in a car outside the Elite Fight Force mixed martial arts gym in Sefton about 6.30am on March 2 and died at the scene.
His 12-year-old son, who was in the passenger seat, was unharmed.
Police later found a burnt-out Mazda about a kilometre away in neighbouring Birrong. The second getaway car, a Volkswagen, was also later found burnt out.
The search for Mr Sabbagh's shooters continues.
Pham will return to court on June 22.
