You don't get to level extremely serious charges against a public figure in this sort of situation and then avoid any sort of questioning and play this, "Maybe I will, maybe I won't game." If you were frightened of being questioned, don't make the accusation public in the first place, which is what she knowingly did by sending the letter to Feinstein. Feinstein's behavior has also been ridiculous with regard to that letter.
I suspect she may be telling the truth, but she and her people are handling this all wrong and she undercuts her credibility with this behavior. It goes without saying that loobing accusations like this and then hiding is also all wrong and I think anyone with any sense of justice and decency recognizes that. This leaves out the campus crazies who actively seek to erode or eliminate the presumption of innocence and the right to face one's accuser in these sorts of cases.