Tell me about it. We have AGMs' with motions directed at controlling drug use and alcohol consumption at the AGM. AGMs can be frightening and we have our fair share of owners who will not come to an AGM.
The stories of disgraceful behavior at AGMs is common to many SPs.
Regrettably the strata gods (CTTT) do not see hostile AGM environments as dysfunctional management.
If your local library has it, a book called Horsley's Meetings is very good for understanding how professional meetings should be handled. You would still need to understand the statutory requirements for strata meetings but if you can put the two together you will at least know what should occur.
You can move a procedural motion — That the agent vacate the Chair and “Joe Bloggs” assumes the Chair; in an attempt to get a Chair who might try to control the rabble. The meeting will need to pass the motion.
Normally it is only people who are entitled to vote who speak on the motions put before the meeting. You could move a procedural motion — That the Chair ejects the non-owners. See how it goes; you will at least be seen to be trying to establish some form of order.
AGMs are not forums for general discussion. They have a fixed agenda and that is all the meeting can determine. You should, if it is not to late, use clause 36 of Sch 2 of the SSMA and requisition some motions so at least what you want discussed gets put on the agenda and discussed.
There isn't much can be done about people giving other people proxies except try lobbying harder to get those proxies yourself.
I know exactly where you are coming from and I look squarely at the poor service provided by the strata overlords for not taking action when this sort of thing occurs year in year out.
If you read Horsley's Meetings you will see a civilized way to have meetings; trying to implement it is another story.
At AGMs in my SP there is always a wolf-pack waiting to consume anyone who is not on-board that groups little bandwagon. It is an occurrence all too common in too many SPs.