As a member of the EC you are part of 'The strata” as you call it. The Strata Manager can only act as instructed by the Owners Corp or the Executive Committee (of which you are part) although they could have offered some advice on this.
You need to put a motion to the EC asking them to
a) Investigate the cause of the flooding and remedy it immediately.
b) If the building is less than six years old, pursue to the developer for the cost of the defect rectification.
The Owners Corp has an absolute and unlimited legal obligation to maintain and repair common property. Other issues like lack of funds and ongoing disputes with builders and developers are irrelevant – the Owners Corp just needs to get on with it as they are legally obliged to do.
If there's any resistance, your next move should be to apply for mediation at Fair Trading, this is a required first step before taking the Owners Corp to the CTTT. Don't worry, EC members are taking action against their own ECs all the time – it's just part of strata living and is often the best way to establish who is responsible for what. You'll get the mediation form HERE.