Final answer:
Henderson's confession develops the plot by revealing the tampering of Multivac's reports and prompting the other men's admission of their actions.
Step-by-step explanation:
Henderson's confession in paragraphs 32-36 of 'The Machine That Won The War' develops the plot by revealing that the other men had tampered with or disregarded Multivac's reports. The confession prompts the other men to admit their actions and take responsibility for the incorrect decisions made in the war. This revelation adds a new layer of complexity to the plot and raises questions about the reliability of Multivac.