Zerahemnah is still in charge. He has been scalped, and no doubt lost blood because of that. Nevertheless, we may suppose that he retired to a more central point in his army, and was bandaged to slow the blood loss. At some point he notes that the situation is truly hopeless, and he signals that he will now accept the conditions of surrender that were first offered. Noticed that he expects that those conditions will still be offered, even though he had previously refused them.