In the same short story, Fi is able to jump on a grenade and come out badly rattled, but alive.
The commandos are appreciative of their armor's durability and it helps them survive many a firefight. There are numerous instances of damage being negated by it.
The characters are either wearing the unbreakable Mando beskar armor, or the cutting-edge nigh unbreakable Katarn commando armor. Arc Words: Vode an - Mando'a for Brothers All.