I’d suggest imagining what the story would look like from the other guy’s point of view, and I bet there would be no malice, no ‘mustache-twirling’ antagonism. It would be about how he always wanted to be a manager, and found a project with a strong technical partner who had no managerial aspirations. How he successfully managed upward and helped to coordinate and keep the project on track. Then at the end, after the success, he got the management role, his partner got to show his technical mastery: everyone got the result they were working toward.