From a GameRant article about models hired to hang around E3 and look interested in games no-one will remember 3 months after launch (colloquially: booth babes) comes the most targeted-and-pointed adbot link I’ve ever seen:
Is the ad for the models… or for us, suppliers of the male gaze??? It’s all so meta!
When even the Adbot is casting judgement, it is time to consider the issue.
World Class Villains 
I’ve not experienced an American games convention but from the horror stories I’d guess such a claim is free money for any of the young women who wish to get a no win no fee lawyer.
Did the employer have a reasonable expectation that the employee might be the target of harassment? Yes. Did he take any steps to protect the employee from such harassment? Quite the opposite.
I can’t see it ever going to court unless however hired the models was promoting fans treat them in a way they actively protested about. Unfortunately being at E3 in hot pants promoting CoD probably means having to deal with some socially incorrect individuals.
EA’s “Sin to Win” promotion (http://www.joystiq.com/2009/07/26/dantes-inferno-team-apologizes-for-sin-to-win-booth-babe-cont/) would have been one that crossed the line, but you’d have to have been hired to work for EA for the best shot.