A REWARD of £20,000 is being offered by the police for information leading to the conviction of those responsible for the vicious attack on a father-of-three from New Addington.
Flyers advertising the incentive are being delivered across the estate today ahead of a reconstruction on BBC's Crimewatch this evening.
Detective Inspector Simon Harding hopes the appeal and reward, which he describes as a "last throw of the dice", will lead to vital new information.
Tonight Zowey Hayward, Gary's sister, will tell Crimewatch that anyone brave enough to come forward will be a "hero".
Gary, 29, was hit with pieces of wood and metal poles while trying to protect his father from a gang of youths in Central Parade, New Addington, in October 2011.
He is now blind in at least one eye, unable to talk and, 18 months on, requires full-time care in a specialist rehabilitation centre.
No one has been charged with the attack and while police have been given names of those involved, no one from the community has yet been willing to give evidence.
"This is the last throw of the dice for this investigation," said Det Insp Harding, "We have come to the point where we have lots of names, people have been arrested in the past but no one has faced prosecution.
"The whole issue for us is to find people who were there at the time who are willing to stand up and give evidence.
"In terms of our investigation, there isn't anything else left other than significant witnesses to come forward and say I saw someone do that.
"We will give those people protection. Whether that's through special measures at court or even anonymity, we will protect you."
Gary was ambushed after he came to the aid of his father John, 54, who had been confronted by a large group of youths as he made his way to the shops on October 2.
The reconstruction will show John walking past the gang – who had been tormenting him for months – on his way to the Booze Bank on Central Parade.
It will give the clearest picture yet of what happened next, including the youths pulling makeshift weapons, including bits of wood and a broom handle, from a nearby bin and attacking the father and son at around 8.45pm.
Gary was taken to King's College Hospital where he underwent an emergency procedure to remove a blood clot from his brain.
He appeared to be making a full recovery but in November fell out of bed while in Princess Royal University Hospital, Bromley, and his condition deteriorated.
Gary underwent an operation to remove fluid from his brain and, since then, has been "asleep", his brain having shut itself down due to the trauma. He now requires full-time care in a specialist rehabilitation centre and may never fully recover.
Police have made four arrests in connection with the attack, but no on has been charged. Det Insp Harding hopes the reward and appeal will "focus" people's minds.
"A large number of names have been put forward and it's our job to corroborate the information that comes in, to sort what's genuine from the rumours," he said.
"The rumour mill on the estate about this attack is enormous. This is now about taking all that information we have got previously, perhaps anonymously, and saying now is the time to step and say I was there."
Det Insp Harding has revealed the police base on Central Parade will be open to the public over the next month to take into account the attention New Addington is likely to attract as a result of the investigation and the trial of Stuart Hazell, the man accused of murdering Tia Sharp, which begins on May 7.
He said: "There will be a great focus on the area, so it's just to give people the reassurance that there are police officers about.
"During tonight's programme we will mention the way the community of New Addington reacted to what happened to Tia. It's the same response that we want now for Gary."Five officers from Croydon will be at the Crimewatch studio taking calls from the public. The programme starts at 9pm on BBC 1.
