The meeting should never have gone ahead.
Proxy votes may not be used at strata committee meetings. Other non-members can represent absent members, but only after the committee has agreed to this and to be able to agree, they have to have a quorum in the first place.
This is what the Act says:
A motion submitted at a meeting of a strata committee must not be considered unless there is a quorum present to consider and vote on the motion.
So all the decisions made at that meeting should be rescinded immediately or mediation requested prior to orders being sought at NCAT.
If the chair and secretary refuse to rescind the decisions and hold another meeting, they should be informed in writing that if they continue to seek legal advice without proper authority, they will be personally liable for the legal bills that are accrued.
Normally the secretary or chair would communicate with lawyers but it can be anyone the strata committee or owners corp appoints in general meeting, provided that person agrees.