Police now want to locate him and speak to him, in the hope he can help their investigation.
It is not known if Miss Rhind had been driving the car but she had been sitting in a front seat.
There are still a number of other questions around the crash, including whether Miss Rhind had been drinking and was wearing a seat belt.
"A crash analysis is underway to confirm if Tatum was the driver and if she was wearing a seat belt," a police spokeswoman said.
"Additionally the speed which the car was travelling prior to the crash is subject to the investigation but it is believed that speed was a factor in the crash.
"Police are waiting on reports to establish whether alcohol was a factor in the crash."
Police have interviewed an injured man from the car, but another young woman involved in the crash has yet to be formally interviewed by police following surgery and medical care.
Fiends and family paid tribute to Miss Rhind this week, following her funeral.
Fitu Patolo posted on Facebook that Miss Rhind would "hold that special spot in my heart, all our hearts".
Leandar Tui said: "I can't imagine my life without you, so I'm still imagining my life with you by my side guiding me. I love you always and forever my best friend."
Younger sister Irirangi Dawson posted on November 11 that she couldn't explain "the pain and emotions" she was experiencing, following her sister's death.
"I'm broken. Our whanau, everyone is ... You were taken away from us too soon. You were not only my big sister but a role model to me."
