"It's just time now," he told the Herald when asked what Rolleston's recovery was looking like.
"His family are up with him in Hamilton because he's in critical care. He's not out of critical yet."
Two of Howe's grandsons had been to visit the young star in hospital to offer their support.
"They're pretty shocked about it, [it's hard] when one of your best mates is in a massive accident like that.
"He's a really popular kid in Opotiki, he's got so many mates."
The other boy, who was part of the same friend group, was also hurt in the crash but was "not as badly injured as James," Howe said.
"He's pretty sore, he's still in hospital at the moment but he's on the road to recovery. So that's a blessing in disguise."
Howe said he was not sure at this stage which of the boys had been driving the car when it crashed.
He described Rolleston and the other boy as being "best of buddies."
On Facebook, messages of support for Rolleston flowed, with his haka group posting a live streamed waiata from Taiwan, where they were performing for a cultural festival.
"This is for a very special person, number two for today, it's for our boy James rolleston," the video began, before a group of people waving and wishing Rolleston well broke into a five-minute-long song for him.
On Thursday, Rolleston's family thanked everyone for their concern through Bay of Plenty District Health Board spokeswoman Diana Marriot.
"The family would like to thank all the well wishers who have sent so many messages of love and support, they are finding this a huge comfort at this time," said Marriot.
Rolleston's breakout performance in Taika Waititi's 2010 movie Boy kicked off his career as an actor.
He also appeared alongside Cliff Curtis in the widely-acclaimed 2014 movie The Dark Horse.
