My Czech friend needs criminal legal advice (Sydney)

Dear internations friends,

I have a Czech friend here in Sydney who's ex-girlfriend (an Australian citizen) has falsely accused him of assault. There are many further details to the matter but essentially his ex-girlfriend had made up with with him, admitted that she was wrong (she has had a history of family abuse, and was imagining abuse in the heat of a argument), and up until last week, was supporting my friend's legal proceedings. However, they've now broken up and she is doing all she can get my Czech friend convicted or deported back to Europe. Unfortunately his student visa is running out, so time is precious.

Can anyone recommend a lawyer, agency, ngo or group who can help him or give some useful advice or contacts? Most people are telling him to just run and leave the country, but he wants to stay, or atleast leave the country without unfinished business. I have met his ex, and I believe any psychiatric evaluation would easily identify her mental illness/abuse history, and the fact that she is lieing. My friend knows he's been stupid for staying with her (love is blind!), but if anything can be done he wants to try and clear his name of a false charge.

Thanks for any assistance,

James