Information on the NSW Office of Fair Trading web page headed Meetings of The Strata Committee suggests notice should have been given to all owners for the SC meeting you mention and ways this should be done. It doesn’t say what to do do if the Strata Committee and / or Strata Manager goes about things in the wrong way. I do hope a clever Flat Chatter knows and weighs in, because we have similar problems where I live all to often.
Also, I’m sure I’ve read here on Flat Chat and in other places agendas and minutes need to be succinct and it doesn’t sound like they were in your case. Again, what’s to be done?