Mr Hagaman's wife, Lani, had signed the contract because Mr Taylor was away at the time.
"I was involved in the whole [process] and I can put my hand on my heart and say I know it was a squeaky clean transaction. There was no favouritism in any way towards it," Mr Taylor said.
Since 2011, the Government has put $18 million into the Matavai resort as part of its efforts to boost tourism to Niue. That included $7.5 million to build a conference centre soon after Scenic Hotels took over.
Labour leader Andrew Little asked the Auditor-General to investigate whether Mr Hagaman's donation to National at the same time his company was tendering for the Niue contract was above board.
"It was Murray McCully's personal appointees on the Niue Tourism Property Trust which awarded this contract ... The perception of propriety is key."
The Matavai is owned by the Niue Tourism Property Trust on behalf of the Government of Niue. That arrangement was put in place in 2011 to ensure oversight of NZ aid.
Mr McCully appoints the trustees who are Ross Ardern (NZ's High Commissioner to Niue and father of Labour MP Jacinda Ardern), Ministry of Foreign Affairs deputy secretary Jonathan Kings and former High Commissioner Mark Blumsky, a former National MP who lives on Niue.