Final answer:
The greatest risk and the next assignment should be to address the payment made for routine inventory items without a purchase order or receiving report.
Step-by-step explanation:
Based on the given information, the greatest risk and the next assignment should be to address the payment made for routine inventory items without a purchase order or receiving report. This presents a significant risk as it suggests that the organization is making payments without proper documentation, which could lead to potential fraud or financial loss.