If the three units in favour have >50% of the unit entitlements, you might be in luck by demanding a poll vote at a general meeting. Alternatively, if the work is clearly necessary, you could go to the tribunal seeking an order to give effect to the failed motion for the special levy on the grounds that it was unreasonable for the motion to have failed. I assume the NSW legislation has a similar provision to the ACT legislation I am more familiar with that allows the Tribunal to undertake a merits review and, if it thinks it was unreasonable for the motion to have failed, give an order to give effect to the failed motion as if it had passed.