Dahlberg's father, Bill, confirmed Robert's bail had been paid and his passport returned to him by officials.
Asked if his son would be returning to Singapore, he replied, "I would think not". He declined to comment further.
Dahlberg had been living in Singapore for about five years and was out drinking with two friends, British man Robert James Springall, 24, and Nathan Robert Miller, 35, an Australian, at Suntec City on April 11 last year when the incident happened.
The three men were believed to be drunk when they allegedly abused two taxi drivers and two passengers.
Dahlberg is understood to have punched a businessman and pushed another man, causing his face to hit a pillar, reportedly fracturing his Nasal bone and cutting his head.
Springall allegedly hijacked the cab and crashed it.
Miller was charged with disorderly behaviour for allegedly jumping on the car bonnet.