Granted what they are doing sounds very unreasonable, and if the consequential loss is due to a CP issue then yes you should be covered.
NCAT does take a long time, which really sucks.
If you have contents insurance (in NSW at least) I would recommend making a claim on your insurance. What should happen is your insurer will write to the OC’s insurance and ask for a no-coverage letter. Essentially this puts the OC’s insurance on notice of a claim and they are obligated to advise if the items are covered or not via the OC’s insurance policy.
If you don’t have contents insurance then I guess you need to go the NCAT route.