Further to my post #283 above I have done a bit more work.
1) I have posted my enhanced video here:
https://imgur.com/KgPtBIN
https://imgur.com/KgPtBIN
I hope that anyone interested can see it. It is at zoom 2X, and Speed 25%, with contrast and saturation increased in a Box around the apparent 2nd Helicopter. In real time, if this video starts at time 0sec, then the rear passenger's shoulder tap would be at 12secs, and the impact would be at 13.5 secs.
2} If anyone has a source for the full "Inside The Helicopter" video without the Channel7 News logo on it, please let us know! The Logo is a major factor in making the video difficult to see in the area of the 2nd helicopter.
3) I withdraw my suggestion that you may be able to see the 2nd helicopter blades flickering slightly. It is probably just the News Logo!
4) But I maintain that it is clear that "Mystery Object" is above and in front of the ground, and is moving left-to-right, which is correct for this to be the 2nd helicopter, to my understanding. It may even be judged to be climbing. And it is generally in the correct position for where the rear seat passenger excitedly points later on.
5) you see the "2nd Helicopter" approaching a building with dark grey walls and a white roof. This building is clearly seen, in the correct relative position, in this Photo of Take-off Helipads cropped from Helispotter Post #58.
6) I also post this drawing of the EC130 helicopter, for comparison.
I hope some of you find this input informative,
IB