Council staff have confirmed the CST moved documents detailing the project's history from an office inside the stadium to a new secure storage facility elsewhere in the city.
The documents were believed to have been moved when the CST moved offices in 2012, after it was decided Dunedin Venues Management Ltd, and not the CST, would run the stadium.
Doing so appeared to contradict a signed agreement between the trust and the council, dating back to 2010.
The trust acted as the council's agent in the stadium project, and the service level agreement between the two parties stated all stadium documents would be kept inside the stadium.
She called for a ''full forensic audit'' of CST spending and claimed it had been withholding information from the council.
On Friday, she sent an email to all councillors, alleging the records were taken from the stadium and ''dumped'' in a container without the council's knowledge.
That could ''thwart'' any attempt to investigate CST spending, and meant the trust had ''essentially misappropriated'' the documents, which remained council property, she insisted.
CST chairman Malcolm Farry rejected the ''slanderous'' claims, saying her views are ''simply not true''.
''When the CST no longer had an office at the stadium, obviously we moved and our records naturally came with us.''
He would not be drawn on whether that was in breach of the signed agreement with the council.
However, he reiterated CST spending went through ''exhaustive'' sign-off and audit processes.
Dunedin Venues Management Ltd chief executive Terry Davies confirmed when contacted the documents were removed in 2012.
''No current staff were involved.''
Council corporate services group manager Sandy Graham said any suggestion the documents had been ''dumped'' in a container was ''absolutely false''.
''They are in a secure storage facility, which I have personally visited.''
The requirement to hold documents at the stadium dated to earlier plans for the trust to run the stadium, she said.
The creation of Dunedin Venues Management Ltd to run the venue eventually prompted the CST to move offices, and the documents moved with it, she said.
''I don't think that's unreasonable.''
They continued to be stored according to best practice, and there were no concerns for their safety, Ms Graham said.
The CST was also continuing to co-operate with the council to provide any documents the council did not think it had, although it maintained the council should already have a complete record, she said.
The ''first tranche'' of 14 boxes of papers had been given to the council, and a second batch was expected this week, Ms Graham said.
Once all documents were copied, the council would hold its own complete record of stadium-related papers, she said.
That would ensure the council could comply with changes to the Local Government Official Information and Meetings Act 1987, introduced earlier this year.
Council chief executive Dr Sue Bidrose is satisfied the documents are safe, describing Ms Butler's claims an investigation might be thwarted as ''groundless''.
''There's no evidence of anything like that having happened, and we have told Bev that on several occasions in the last fortnight.''
