If you look at the detail of the law, it says that either the committee can instigate a request for penalties, provided that decision is taken by majority vote at a properly constitute committee meeting, or the strata manager can do so provided they think a bylaw has been breached.
It may be that your strata manager wanted you to pass a motion at a committee meeting before they were prepared to act on the complaint, having not witness the breaches themselves (although that might be considered nit-picking).
Have a look at this information from Kerin Benson lawyers, which lays out the detail of how to issue a Notice To Comply.
And have a look at this information from our sponsors Bannerman Lawyers which explains the timeline for the two options – going directly to NCAT or attempting mediation.