The 29-year-old man is due to face court on Friday after being charged with murder and wound with intent to cause grievous bodily harm.
Police allege he facilitated the gunpoint abduction of a 45-year-old woman from her Bankstown home in Sydney's southwest, assaulting her eight-year-old son with a baseball bat during the April attack.
The woman's body was found in a torched car about an hour after the alleged abduction.
The shocking crime was believed to stem from a dispute between the woman's de facto husband and an interstate organised crime group he allegedly worked for.
"These organised crime groups are breaking their own code of conduct by targeting innocent women and children," NSW Police Detective Superintendent Joseph Doueihi said at the time.
As many as five men were believed to be involved in the woman's kidnapping and murder.
The woman had no criminal record, while her male partner was known to police for minor drug offences.
Police said he was interstate on business at the time of the attack and was co-operating with the investigation.Â
The eight-year-old boy needed emergency surgery for serious head injuries and was in an induced coma for days following the attack.
He is expected to suffer lifelong complications from his injuries.
Investigations are continuing as police look for others allegedly involved in the woman's murder.
