I’m a little late to this thread but ….
As I understand from recent experience and research of this issue, there is a clear process that prospective tenants are expected to follow before they bring an animal into a strata scheme:
First, they need written permission from the landlord. The OP says approval was given by the agent ‘and obviously the owner’. However, it is not so obvious as the OP has explained it here. It is not clear that a specific request was put to the landlord and that written approval was then provided by the landlord. The rental agent has no authority to give consent.
Assuming that the OP did in fact receive approval in writing from the landlord, the next step is to write to the OC via the Strata Manager requesting permission for the animal, including a copy of the written consent of the landlord, and as much detail as possible about the animal as to its size, breed, character, vaccinations, micro-chipping, how waste will be managed, how it will be exercised and so on.
What should not happen is that the prospective tenant just moves in with the animal without written consent of the landlord and without written permission from the OC, and simply pretend that fait accompli will prevail. This is a cyclical ploy by prospective pet owners in strata that seems to be occurring with increasing frequency. It is a tactic that NCAT or any other body charged with oversight of strata living should actively discourage by not rewarding it with favourable rulings.
A tenant who simply arrives with an animal and makes no prior application for consent from the landlord and makes no application to the OC is in beach of their lease and in breach of any by-law that might apply to the scheme with regard to animals. Such a tenant has not acted reasonably and should not simply expect to be granted retrospective consent to the animal when they are duly alerted by the OC to cease acting contrary to the by-law and the terms of their lease.
If such a tenant then continues to house the animal and makes a retrospective application to the OC, it is surely not unreasonable of an OC to refuse permission given the tenant’s obvious failure to respect the terms of their lease from the outset and failure to meet the minimum reasonable expectation of a prospective pet owner.