I think this is more about, what was potentially about to be, both continued as per normal, controller stepped in alerting the departure aircraft around upcoming conflict and they then tracked north east. If they didn't, they likely would have continued upwind until they got a TCAS, that is my impression after looking at the archive, did not seem to be any concern re conflict, and both seemed to be aware of each other, both continued on as normal. They only started talking to each other when a separation issue was about to be raised by the controller.
This one might be a good example around airmanship, communications between other aircraft within the TIBA. If the departure aircraft decided to wait until the Jetstar arrival had landed, they also had another one to deal with behind, would have been 15 minutes wait at least. Sometimes you just gotta wait.
I reckon the controller might have lodged the case around this one not the crews.