The ostler fails to rescue horses because

At last I heard steps outside, and the hostler who had put up the traveler's horse burst into the stable with a lantern, and began to untie the horses, and try to lead them out; but he seemed in such a hurry and so frightened himself that he frightened me still more. The first horse would not go with him; he tried the second and third, and they too would not stir. He came to me next and tried to drag me out of the stall by force; of course that was no use. He tried us all by turns and then left the stable.