2. I think most banks which allow 0 balance completely digital savings account, dispatch the kit only when they are able to deduct the charges from your account (200+GST in this case) which can only happen once you fund the account. I have a feeling you haven't funded it yet which is understandable since you never wanted the savings account in the first place. So, call/mail the customer care to let them know that you don't want a debit card for your account, if you wish to continue the savings account or ask them the steps to close the account. Upon referring to the services fees document, there was no mention of closure charges, so, it's safe to say, you won't be charged anything for closing your savings account.
1. and 3. I have no idea, never had a savings/FD account with AU.