There are three hydraulics systems in a 767. A leak in any one, even if all the fluid escapes, does not even require a diversion to nearest suitable let alone dumping fuel and declaring a Pan. Fair enough he was close to Sydney and no doubt he got on the radio and asked advice and maybe they said 'we'd like you to land here and we'll fix it'. The fuel dump would just be QF SOP, my company would not expect that unless I was over 170 tonnes, on a long runway....short/wet runway very different story.
Had he been over Ujung he'd have likely kept going to Manila and no one would have heard about it, not even the pax. This is a non issue blown out of all proportion by irresponsible media.