You're leading a hybrid financial services project where the product team works in two-week sprints while infrastructure changes follow a stage-gate process due to strict change control requirements. A senior developer who has been with the organization for 12 years is resisting the agile practices, insisting that 'proper engineering requires complete upfront design.' This developer's influence is causing other team members to question the hybrid approach. In the last sprint review, this developer publicly criticized the incremental delivery model in front of executives. The product owner has privately asked you to remove this person from the team. What is the most appropriate action?