Fair points in your last paragraph.

While I understand your point I think we also need to think in a very pragmatic way. Those soldiers in the story had orders and can't act on their own gut feelings. Taking a stance here would have had so many implications.

I don't see a way where France would not be blamed. If the French army had taken a strong stance and toppled the Rwandan power, I don't know if it could have prevented anything in terms of civil war and massacres, but it would have been sure to create a power vacuum in the middle of a bloody civil war from a western former colonial power.

I guess the best option was to leave completely, impose fast sanctions, and not get involved further. Still a massacre with a loss of influence as well for the aftermath.