No one has really given an answer besides what you've stated. Personally, I have no idea what the best option is; my cynicism tells me that making it public may be the best course of action, though it's a very scorched-earth approach. By making the harassment known publicly (within the workplace, possibly outside), it forces HR's hand in dealing with the abuser rather than the abused. It also has a chance to backfire spectacularly and alienate the person. It probably would result in alienation even if the abuser was dealt with. There's really no good answer here, just varying degrees of bad ones. Perhaps there needs to be a fine against companies that attempt to silence/remove the victims, that'd create a financial incentive for HR to protect the company by removing the abuser.