inter arma silent leges
Amidst arms the law is silent.
The article destroys its own premise. Civilians in battle will almost universally seek to flee. If they do not, and do as indicated in the article, which is take an active part in the game/battle, that is as a combatant, then they lose any and all protection they might receive under the laws of Jus in bellum (justice in war, which is not jus bellum, just war) but they forfeit all moral consideration and mercy and no matter how ill-equipped or untrained legitimate targets who like enemy soldiers can be killed out of hand and so forth.
In such cases there are no moral decisions to be faced. An enemy armed and dangerous be it a man, woman or child, not as a member of an armed forces by taking up arms makes himself one and is a legitimate object for extermination. The presence of civilians in and among the enemy is simply collateral damage. They are protected by the laws of war only to the extent they are given a chance to flee.
IF I was in real war, a civilian of the enemy population with a gun in his hand I would shot outright without a second thought. A civilian of the enemy population without a weapon I would probably scream at them "get in the cellar you stupid idiot" and kick them down the stairs. A civilian who came to me as a commander and asked for help freeing trapped people in a cellar I would help with as many men I could spare, and if I could spare none, then I would simply say "My empathy, sympathy, and prayers go with you, and perhaps in a little while I can be of more assistance."
In my game I form civilian units in a different way.
All of my units are color coded on their base tag which contains all the combat abilities of the unit. Civilian units are all color coded white
This is a clear signal to the players that these units work for the GM and therefore should be avoided like the plague. This goes for all players, those from the same side as the alleged civilians, those from the other, and if the civilians know what's good for theselves, from each other as well.
Some Civilian units are
Mademoiselle LeBimbeau on bicycle. (You've seen The Longest day.)
The scrappy ratty little street urchin called "Kid"
Ilsa She wolf of the SS and here pet Doberman Blitz Fritz.
It's a game. I leave the sticky morality behind.