Signing away your lawsuit rights is a part of basically every single dangerous activity though, and is not unique to overseas employment with Halliburton.
It's not clear why this person is going after Halliburton insteadof/in addition to the 4 persons responsible. Why a civil case against Halliburton? Because Juries throw out the big bucks, I guess.
PS: in the US, if 4 union members had raped this woman at the request if their union boss, the union would be legally sheilded from any prosecution for any wrongdoing, so long as the union could make the case that raping the woman was in the pursuit of legitimate union goals.
Halliburton does not have a policy of telling its employees to gang rape women. Many unions do have a policy of intimidation or violence against targets of opportunity.
I can't decide if Franken is trying to do this for the right reasons and is just dimwitted about the legal realities of this kind of sitution, or if he's grandstanding against Halliburton with an appeal to emotionalism.