NSW Not for Profit Sporting Club - Unfair Exclusion and Breach of Privacy?

Can someone please advise our sporting club on this matter.

A overdue account owed by our club was forwarded on to a unauthorised third party.
There was no contact made to our club in reference to this account.
The third party is the sports governing body who contacted our club.
The account was paid in full immediately by our club.

The problem we now have is that the third party - governing body,is using this information to have our club excluded from the competition. We have two (2) weeks before the commencement of the competition and we have many sponsors that have donated money to use for uniforms, equipment, supplies etc which the club has done so.

The club is to front a meeting tonight and explain why we should still be allowed entry into the competition then all the other clubs and executives will have the right to vote for or against us.

We feel that this disclosure is a breach of the privacy act and would like advice on how to stop the third party from disclosing the information about this account at the meeting tonight.

We are a not for profit organisation that runs on the smell of an oily rag. We cannot afford any legal advice. And we believe that if the club is excluded in tonight's meeting this will cause undue embarrassment and financial duress to the club and it's sponsors.

Thank you for your help in this matter