I had this experience several years ago. Here is what happened. A lot owner breached Section 108 of the Strata Schemes Management Act 2015 (NSW) by attaching something to the exterior brick wall. Our strata manager had two meetings with the owner, requesting the illegal structures be removed. Lot owner declined. Strata manager then applied for mediation with Office of Fair Trading NSW. The Office sent multiple invitation letters to the owner. The lot owner declined / did not respond to the invitations. Then the strata manager applied to NCAT on behalf of the owners corporation. NCAT ordered that the structures be removed and the owner pay for the cost of repairing the damage. i.e. fill in the holes in the bricks. The whole process took about nine months.
We had to have evidence of attempted mediation before making the NCAT application. Mediation through Office of Fair Trading is slow (months). Maybe there are other ways to show that you attempted mediation?