Before you take this matter to NCAT you would need to show that the OC has refused to undertake the work.
It is unclear from your comment whether these options for repairs have been raised in a Motion with Alternatives at a General Meeting, and voted on at a General Meeting. If these options have not yet been voted on at a General Meeting then there would not be sufficient grounds at this time to take this matter to NCAT, in my opinion.
However, if the issues of repairs and the raising of a special levy have been previously voted on and the majority vote was NO then you may have a case to take to NCAT. Can you please advise what actions have been taken to have this matter resolved so far?
From SSMA 2015:
106 Duty of owners corporation to maintain and repair property
(1) An owners corporation for a strata scheme must properly maintain and keep in a state of good and serviceable repair the common property and any personal property vested in the owners corporation.