McFarlane said he had since offered to meet with both sets of parents to discuss the matter.
He said: “This has obviously come as a huge shock to everyone and we recognise the additional trauma this may cause.
“We are supporting Trevor and all the families through this and have engaged specialist agencies to help provide that support.
“I have also offered to meet with both sets of parents as I am sure they will have many questions, most of which we are not able to answer yet but we are absolutely committed to understanding how this happened so it cannot happen again.”
He said South Yorkshire Police would fully cooperate with any subsequent investigation by the police watchdog.
Wynn was not named publicly by police at the time of the crash, but was widely identified on social media and in local news outlets as having died in the collision.
The 17-year-old girl has not been formally named.
An 18-year-old who was arrested on suspicion of causing death by dangerous driving and a 19-year-old arrested on suspicion of perverting the course of justice in connection with the crash both remain on bail pending further enquiries.
The IOPC said it was assessing the referral to determine whether an investigation was required.