Official records about the shaky state of the prized Carillon bell tower have been "splintered", making it harder for the public to find out what is going on.
The Ombudsman has found the Ministry of Culture and Heritage did not "deliberately" withhold information from RNZ, but that it gave an "inadequate" response that left out key documents due to a series of internal shortcomings.
The Carillon in central Wellington has been closed since early 2020 because it is an earthquake risk.
It has a deadline to be fixed of May next year but that looks almost certain to be missed.
RNZ understands the ministry is now aiming for reopening in time for Anzac Day 2023.
RNZ complained to the Ombudsman about the ministry's response in twice leaving information out in response to OIA requests in 2020 that revealed just how patchy the years-long project to fix the tower has been.
The ministry apologised to RNZ, provided the information and told the Ombudsman it would do better.
"It appears as though MCH's [Ministry of Culture and Heritage] record keeping regarding the Carillon instrument restoration project is splintered and this made the search for information difficult," chief Ombudsman Peter Boshier said in his recent finding.
It had good processes but had not followed them, Boshier said.
Officials had relied for a key document on "an old desktop" computer at a staff member's home that was not networked, but had been "rescued from the tower upon [its] closure in February 2020".
A work plan was sent to RNZ minus financial information, with the ministry saying it simply did not know why this was left out.
In another case, it had done a "cut-and-paste" job that left bits out so "as such there was no decision to exclude the documents", it told investigators.
Some documents had similar titles, or various versions, leading to "a high chance of human error".
"Any implication or inference of nefariousness on the part of the ministry would be inaccurate," the ministry told RNZ.
The Ombudsman and ministry spoke about the trouble meeting tight deadlines.
The ministry listed a bunch of actions it was taking to improve, including training staff and making them more "aware of their obligations" to the public.
"Responding to an OIA request is now a significant part of its induction programmes for new staff," it said.
"New staff members are provided IT training which includes information filing management. It has also reminded staff about storing information in a more easily accessible way."