Bids for the convention centre were also made by Auckland-based iwi Ngati Whatua and ASB Showgrounds, a consortium led by infrastructure company Infratil and The Edge.
Ngati Whatua chief executive Tiwana Tibble said SkyCity had been given an unfair funding advantage because of the Government's promise of an extended gambling licence.
But he did not begrudge SkyCity its advantage: "I lobbied to the PM, I went and saw him a couple of times. It's a $350 million contract, that's what people do.
"They don't just stick a tender in the envelope and hope for the best."
Mr Tibble confirmed that Ngati Whatua would bid if the process was reopened, but he felt that calling for tenders again was "a waste of taxpayers' money".
Spokesman for The Edge Paul Brewer said the company felt the tender process had been robust at the time.
The Edge would not bid for a convention centre again, because its role had changed since being absorbed into a council-controlled organisation.
ASB Showgrounds chief executive Mark Frankham said that while SkyCity's proposal to pay for the convention centre gave it an advantage over competitors, he had no concerns about the tender process.
"We've been involved in a lot of tenders. This one was done with the utmost efficiency."