Outsourcing Arguments?

Question

Career in IT

Good morning!
I want to briefly state the problem: Our company consists of many subsidiaries and affiliates, the company where I work has developed IS for procurement, tenders, etc. And now our parent organization wants to take this system and give it to another company from SDCs, arguing that that company is more focused on IT. The profile of our company is purchasing, how to tell the management of the parent company that this is a bad idea? It's like outsourcing a system.