It might be a long term deal in which case he could re-locate. Otherwise it is closer because Sydney to Melbourne is one of the busiest air routes in the world. Not only is the distance shorter and you don't have to go through international clearance but you can pretty much just turn up at the airport and find a flight. His family could fly in to see him every weekend that he's not in Sydney, he could fly back for the odd day here and there. I work with people who commute between Melbourne and Sydney (the other direction from Rudan) and it works for them.
Also with WM playing out of Geelong for a few years, you are pretty close to the tin shed domestic airport at Avalon (midway Melbourne and Geelong). Last time I was there (admittedly 7 years ago) you could literally park your car long term outside the terminal gates.