Take it and return to complete the last challenge. If you are low on health, simply webswing back to the area of the previous fight and the health icon will still be there. If you end the second to the last battle with most of your health, do not pick up the health icon that appears. The last battle of a Combat Tour is the hardest.
He will be there depending on how many races you have acheived medals in. Locate the Human Torch icon on top of the Baxter Building in Manhattan it's the tall white building.