Earlier this week, police released CCTV footage of a vehicle police hoped to identify.
Ryan's father, Nathan Phillips said yesterday his son's condition continued to progress slowly.
On Tuesday, doctors brought Ryan out of his induced coma for about 30 minutes but he was then placed back under sedation, though not as deeply as before.
"He is pretty much the same as yesterday. He came off his medication a little bit but was put back under again because he was unable to hold enough air in his lungs."
Despite still being in an induced coma, Ryan's level of sedation had been reduced, Mr Phillips said.
"The doctors are being very cautious. They are just trying to get his lungs to inflate and hold more air by himself, rather than have the machine doing it for him."
Police are not seeking anyone else in relation to the incident.