The calls are coming from the operator -- and that's not anger. That's the anguished cry of a man who knows his career and livelihood have just ended. Maybe the accident was his fault, I dunno, but it doesn't bring me any joy.
These rich fucks will sue the crane company, and between that and insurance they'll get all of their money back plus some. The ultimate loser here will be the operator. He's fucked for life and he knows it.
Even after re-watching this several times it's hard to tell exactly what transpires. I'm pretty sure though that you can hear the operator yelling before the first crunching sound.
My conclusion so far is that the operator begins to yell as he feels the back end of the truck lifting up off the ground, followed almost immediately by the arm crashing through the roof of the garage. If that's the case, then this may be the result of mis/poor calculation of the torque this thing would exert instead of a failure of part of the crane. If so, the operator really is fucked.
Almost certainly there is a computer program that they use figuring how much weight can me held at what angle and distance from the crane's ballast. Since doing that calculation is what the computer's for, I'm sure they're blaming the computer for the wrong information they put into it.