It probably is too much to ask. Optus have really dropped the ball with this one. Explain your complaint to the TIO, they'll ask you what resolution you want. Optus will eventually contact you and you'll eventually get a non-faulty replacement. Don't bother in store, they'll just give you the run around.
I'm not sure, mate. You'll have to ask the TIO if they do that. Sorry I couldn't help you there. But definitely get them involved with your complaint, they'll get the ball rolling with your issue with Optus and help get it sorted for you.