Reading between the lines of Mrs. Fowler's account, the company's goal was being nice to a more important employee than her: a common situation in sexual harassment cases and other workplace conflicts.
They have a management chain just like everyone else, and if the person at the top (or the person above them) says "We're not going to discipline this guy" then the best HR can do is try to deescalate the situation.
If Edward had to do it, we do too.