The timeframe of the traffic being delivered to the appropriate aircraft is moot. What's to say anything different would have happened had the aircraft had the traffic 10 minutes earlier? It's basically up to the pilots to arrange separation in this scenario. Why? Why should they be doing this? Class E would have had those aircraft positively separated. No prang.
This accident was caused by inappropriate airspace classification for the density of traffic.
Dick, I'm told that ASA haven't got a problem with being told to implement Class E, everywhere. That it's CASA getting in the way of it all.