Immediately call an EGM with one item on the agenda: “Removal of non-compliant committee member.”
At the EGM, the votes of 75 per cent of those attending, in person or by proxy, can remove the member from the committee.
Under Section 35 (1)(e):
An elected member of a strata committee vacates office as a member … if the owners corporation, in accordance with a special resolution, determines that the person’s office as a member is vacated.
Immediately hold a committee meeting afterwards to bring in a new committee member who has already agreed to sign the document (this is by co-option by the committee, not full election).
I’m guessing the the prospect of being publicly kicked off the committee may nudge the recalcitrant member towards signing if he or she is able to do so.
By the way, I have never before heard of this being a condition for getting insurance but I can’t say it surprises me.