Former Treaty Negotiations Minister Chris Finlayson says Thursday's Ihumātao hīkoi to the Prime Minister's office is heading in the wrong direction.
Instead, they should be marching south to meet Tainui, who could step in with a "win-win for everyone" should they wish.
Protesters occupying the land in south Auckland are going to deliver a petition to Jacinda Ardern's electorate office in Mt Albert on Thursday, marching four hours from the site at the centre of a long-running land dispute.
They say it was confiscated in 1863, and should be returned to its rightful owners.
"It really speaks to the beginnings of our nation," protest leader Pania Newton told The AM Show on Thursday. "It's significant to the people here and we think it should be protected for all New Zealanders to enjoy."
But Dr Finlayson says the Prime Minister - who has rebuffed prior invitations to visit the protest - has done the right thing in staying out of the fight.
"The hīkoi should turn around and not march to the Prime Minister's office, but march down to Tainui," he told The AM Show on Thursday, saying the solution to the standoff is "blindingly obvious".
"All the iwi that have settled around this area have Tainui links. Kiingi Tuheitia's been there. I think it's a fantastic opportunity for Tainui to step up - they're very, very wealthy - and say, 'Right - we'll buy the land commercially. Nothing to do with the Crown at all.'"
Tainui was the first iwi to cut a deal with the Crown in the mid-1990s, and has since turned its $170 million into holdings of more than $1 billion.
"They could think about an appropriate development there that takes into account all the concerns Pania has mentioned," said Dr Finlayson.
"You could get an appropriate Novotel there, beautiful open space. Someone suggested it could be a golf course... Open space, beautiful piece of land. What better than having 18 holes before you jump on the Emirates flight to Dubai?"
Dr Finlayson, having looked through property deeds, cast doubt on whether the land was actually confiscated in 1863 as the protesters claim.
"But it was still confiscated - that seems to be the case - although there's some debate about by whom and when."
Asked why the protesters hadn't asked Tainui to flex its financial muscle, Dr Finlayson said it's because the "kneejerk reaction" is always "go to the Crown".
"I rang [then-Treaty Negotiations Minister] Doug Graham the other day, and said, 'What happened when there was the Moutua Gardens occupation?' He said, '[then-Prime Minister] Jim Bolger and I stayed a million miles away from it.' And that is exactly the right thing.
"With the greatest of respect, the Prime Minister is doing the right thing... there is a commercial deal to be had here that is so blindingly obvious, that's a win-win for everyone."
Fletcher would be happy to take the money and run, rather than fight it in court, said Dr Finlayson.
"That would only be the battle of Agincourt, so why go there?" he said, referring to the 15th-century battle when a numerically superior French army was routed by the English.
In nine years Dr Finlayson settled 59 claims - more than any other Treaty Negotiations Minister.
The AM Show / Newshub reporter Dan Satherley