Situations where Commander Zhalk can't beat three level 1's, or is deadlocked against two, shouldn't exist. Yeah it's EA, but this stuff has persisted for a full year after release.
To be fair, he does get backup eventually (if you take too long, two more cambions show up), but it is indeed one hell (pun intended) of a design oversight.
Off-topic, but they really need to do an enemy level reassessment by the time the game is ready for release and there is no longer a throttling lvl 4 cap. Zhalk should have extra attacks. Ethel should be much at a much higher level (even without tweaking her HP, but with more dangerous spells) if she's supposed to be an ancient hag. There are hints of there being at least some kind of sensible CR going on with the Grymforge guardian who is level 8 (but should probably be higher too), but then Voss' red dragon friend who was at level 17 before now got tuned down to 10 for some reason.