Its a long period, he must get acceptance/refusal email/letter etc. If the email was entered in forms, make sure to check email inbox, specifically Spam Box. E-mail is most common way of communication from CIO now days.
If nothing works, ask them to contact their Local Visa Office/embassy as soon as possible, if file was accepted at Sydney stage, that it must already forwarded to your regional visa office. Embassy/Visa Office hopefully will able to help in this matter.