There is no way to let line out fast enough to save unless it is a friction crane so you can just dump the load and even then it the line is parted at all it will not come off the drum fast enough.
This crane operator just bought a crane out of stupidity. I noticed that when the log hit the ground initially it hesitated before it took it all the way down. I would hope that he would calculate the weight of the log and check his charts and setup before doing a lift again.
I am a certified crane operator and have a license for just that type of crane. any of you that rent a boomtruck or any lifting device, forklift or whatever, know the chart that comes with it and obey the rules. Do not be intimidated by your employer and do it because he/she tells you to. When you make a lift as an operator, you own the load, you are totally responsible for the load, machine, and the safety of the folks around you.