> The consultant is being paid by management. S/he is beholden to them.
Quite the opposite. One of the reasons people go into consulting (and I don't mean working for a consulting company), is precisely because they're not beholden to them. They have much more freedom to set the terms than employees do.
If a company wants them to reveal the individual, they'll be happy to give them the middle finger and let them know their morals are lacking.