... can anyone find a link to the safety/CBA for the flightwatch changes??
Nope, there is no CBA - in any case, it would be kinda hard to justify the changes to eliminate only 2 flightwatch staff.
More importantly, has CASA run the ruler over it?
It is another ATC managed "situation" that will "integrate" the vhf fightwatch service and ultimately provide no service at all.
Case in point? Look no futher than the "ATC-initated FIS" and Hazard Alerts debarkle.