The pack howitzer can not kill full health squads. It'll do an absolute maximum damage of 68 in the near AOE iirc. Only the scott is still capable of actually killing models in one shot for whatever reason.
Yeah looks like your right there. Still spreading it's damage out more evenly would be a good change IMO. Its near radius is larger than other indirect units
Also the HEAT barrage does 160 dmg so that is capable of full-health kills. I think in a decent radius as well, at least 2 if not more