This study proposes an interoperable Management Information System (MIS) that integrates real-time payment intelligence, merchandise planning, and distributed workforce coordination within a unified enterprise information architecture. The proposed framework addresses fragmentation across payment, retail, inventory, and workforce systems through System, Process, and Experience APIs, supported by Apache Kafka and Apache Flink for real-time event processing. Synthetic financial, retail, and workforce datasets are used to evaluate payment-event processing, fraud aware demand signals, inventory decisions, workforce allocation, operational reliability, and governance. A multi-objective planning model considers processing latency, inventory exposure, workforce imbalance, and operational risk. The experimental results indicate that the proposed MIS achieved 86 ms decision latency, compared with 420 ms for event-driven processing and 1,850 ms for batch coordination. Timely payment event processing reached 97%, inventory response reached 91%, and workforce task response reached 88%. The findings indicate that payment activity can serve as a real-time operational signal for merchandise and workforce decisions when supported by governed interoperability, event processing, and audit controls. The study provides an architecture and evaluation framework for integrated decision intelligence across distributed enterprise operations.