From the link in post #1 it would seem a taxi onto stand and a push-back collision. One suspects the onus is on the push-back crew. Surely they had a chappie on the headset monitoring the area behind? It seems night?
How does ATC do it at LAX? In UK ATC would say "behind (or after XYZ has passed) cleared to push." The captain would repeat this to the push-back crew. Is it that LAX gives clearance and the onus is on the push-back a/c to do so when safe?
It's a bit like being given clearance to land when No. 2 on finals and still one on runway as well. You are cleared to land, but it is your decision to decide if it is safe to do so. At least that's how it was in 90's when I last stepped a toe into US ATC territory.