So, even when Marcone has been his composed self, the Fallen must have been terrified and trying to force him to just leave Harry alone. Because if Harry could gather an ounce of his power to throw the Spear to him he would not even need to walk to it. The risk was too high.
Which again, reminds me that the Spear is not mentioned at the end, we don't know what happened to it. Perhaps Justine took it. Perhaps a Denarian. Perhaps Harry took it for a secret purpose and does not tell the readers.