Guyton, the former North Otago, Blues and Māori All Black player, who died of suspected suicide last year, had a degenerative brain disease linked to repeated head knocks.
The 33-year-old was said to have had 17 concussions and was diagnosed postmortem with stage 2 chronic traumatic encephalopathy (CTE).
His father, John Guyton, of Waimate, has now teamed up with former All Black Carl Hayman, who has been diagnosed with early-onset dementia and probable CTE, to raise further awareness about the risks of repeated concussions.
Mr Guyton hoped speaking out would help prevent other players from going through what his son did.
"If we had understood what it was, if Billy had understood, then his life didn’t need to be the way it was. It tore our family to bits."
Mr Guyton did not think the New Zealand Rugby Union was doing enough to reduce the risks.
"They’re hiding in the corner like coward dogs.
"The feedback we’ve got from the public is everyone wants to see change, that I’ve spoken to.
"It appears the New Zealand Rugby Union are the only ones that are not connecting all this together."
A New Zealand Rugby Union (NZR) spokesman said it was still unsure if there was a direct link between repeated head knocks and CTE.
While there was debate about the link, what could not be disagreed with was repeated head impacts were a safety risk in contact sports like rugby.
"NZR continues to prioritise reducing and mitigating that risk to participants at all levels of the game.
"We are committed to always doing more and are responsive to developments in both science and best practice."
NZR was at the forefront of concussion initiatives globally in both professional and community rugby, he said.
In 2002 it began the RugbySmart programme to educate about player safety.
It was mandatory for all coaches and referees to undertake RugbySmart training annually.
Mr Guyton said he understood "they’re trying to protect their game, but they’re actually going to damage it more".
He likened it to American football in the United States.
"Since they [addressed the issue of CTE] and went public with it, the game has actually got stronger than it was."
At the core of his fight, he wanted to prevent other families from going through what his had.
"Billy’s already gone — there’s nothing that can bring Billy back. But we can help these other guys."
"I suggested to them that we got together and have a meeting rather than them working against us.
"We’ll see where they’re going with it.
"If they’re not going to go in the right direction, we’ll go in another direction to get this out in the open."
With or without the association, Mr Guyton would continue to raise awareness for CTE.
"If they don’t support us or back us in what we’re doing, I think we’re going to do it anyway.
"We’re going to get out and educate people and players and their families. It’ll be interesting days ahead."
His biggest issue was the players association minimising the seriousness of CTE in the information they gave to players.
"They’re watering it right down. They’re making out soccer is worse than rugby and just melting it down as if it’s not as serious as it is."
A New Zealand Rugby Players Association spokesman disagreed they were minimising the risk, but were open to hearing Mr Guyton’s concerns at the meeting.
"No-one is going to minimise this", he said.
"We are going to incredible lengths to get as much information as possible to the players."
