I'm neutral, but I agree. There's always a non-zero chance that any software, network, system can and will be exploited.
Explain how to exploit it then.
It may not be proven in practice because there's probably not enough incentives for hackers to attack and exploit those coordinators. But on paper? You can't say that the system is "perfectly/100% not exploitable". That would be dishonest.
Explain how to exploit it then.