If this were the ACT, then the person to whom ownership passed would have to have notified the OC that they were now the owner and have provided their details for the unit roll in order to be eligible to vote. I expect an heir in such circumstances would have to show evidence that title to the property had been transferred to them before the OC would record them as the owner. Where there are more than one owner on the unit roll, one person must be recorded as the person who will act on behalf of those multiple owners, including voting.
Alternatively, if title has not yet been transferred but the deceased owner had appointed someone as their proxy, then I think that proxy could vote.
I don’t think an heir who is not yet on the title documents, who was not appointed as proxy, can just put up their hand and claim a right to vote.
I don’t think it matters if someone who might not be the owner has paid the levies.
The above is what I think would apply in the ACT and I am just guessing that Vic would be similar.