In UAV-IoT systems, trajectory planning is crucial for maintaining effective communication, coordination, and energy efficiency. This challenge is further compounded when UAVs need to coordinate with IoT devices and maintain continuous communication. Existing approaches struggle with limited scalability and inefficient energy management in UAV-supported IoT networks, leading to increased latency and reduced data throughput as network size expands. This work introduces an energy-efficient framework using a multi-objective PathFinder algorithm designed to simultaneously handle transmission coordination between drones and IoT devices. The proposed approach facilitates collaborative decision-making for route planning and resource allocation by utilizing the Collaborative Index, which measures cooperative behavior among network nodes, emphasizing key node cooperativeness parameters. Furthermore, a multi-objective fitness function was constructed for effective path planning using the Collaboration Index of nodes in the path and the QoS of the path. To validate the efficacy of the proposed model, a series of simulations were conducted focusing on key performance indicators such as energy consumption, data delay, and task completion rates against existing state-of-the-art methods.