The bolded is far too deep in metagame-side thinking for my liking.
If memory serves (this was 17 years ago!) the trap did something like 3d6 damage to anyone caught beneath it when the rocks came down. Most 1st-level characters in our game have between 5-12 hit points; and death is at -10 (at 0 or below you might be unconscious). The simple math there says death is unlikely but possible while getting knocked below 0 is fairly likely - if you get hit.
Then the dice took over. Natural 20 for the Ogre's "aim" with the trap; crit roll gave 4x damage, and the charaacters were bunched together. 11 points damage became 44 (I remember those numbers clearly!) and at 1st level there ain't nobody gonna survive that. Of a party of (I think) 9 at the time, 4 died on the spot and the rest fled. (after doing some recruiting they went right back there and took out that Ogre)
Same thing could have happened had the Ogre got a 4x crit on an attack, except it would only kill one character at a time.
Unfair? I don't think so. Unlucky? All day long.
To the bolded: it's not my place to tell people how to play their characters. Full stop.
Never mind that the infighting is where all the good stories came from, still told and laughed about today.