Appointment and nomination are different. Obama appointed DeMarco out of necessity to replace by law Director Lockhart who had resigned. Obama chose one of the candidates dictated by law who could succeed the absent Director. So he did not pick DeMarco because he saw him as helpful or useful but because the law said fill the position when it is vacated. Obama did not bother to find a nominee of his choice that would have to be confirmed by the Senate. He appointed DeMarco by law and so the Senate did not and needed not to confirm DeMarco