The problem here is that this expression can only produce 1 or 2, not 3. It should be changed to 3 instead of 2, to use all three variations of each weapon sound.
The line in question appears twice in events.js, once for the player's attack and once for the enemy's attack, which I missed last time. Still, it hasn't been fixed yet.
https://github.com/doublespeakgames/adarkroom/blob/48ece588ed65e3c1c412ee57143ef447185cd0c9/script/events.js#L425
The problem here is that this expression can only produce 1 or 2, not 3. It should be changed to 3 instead of 2, to use all three variations of each weapon sound.