So, if the SM refuses to act, can the SC Secretary issue the NTC without holding a meeting?
If the Strata Committee and/or strata manager have delegated powers from the owners corporation then either can issue Notices To Comply. The SM can do so off their own bat, the strata secretary can do so if their has been a committee meeting approving the issuance of the NTC.
Delegated powers are pretty standard and are generally agreed at every AGM without discussion or dispute. I would be very surprised if your scheme doesn’t have them.
However, if that’s the case, hold a general meeting now, delegate the powers and issue the NTC at the same time. It really bothers me that your strata manager isn’t either following instructions or giving you this advice. What are you paying them for?
In the absence of an NTC option, you can seek mediation with the renovator with a view to getting a stop-work order at NCAT.
If you don’t do anything the renovator will pop up in acouple of years expecting you to fix common property, saying your committee knew the renovations were going ahead but did nothing to stop them.