Again, what the tutorial NPC says is that there's also a chance for enemies to not take an action based on the differences between agility. Not that it only affects the order of turns taken, but that a high relative agility on Karryn means that enemies might not take an attack, but almost always get an attack the turn after they miss one.
Now, I don't know the coding side of anything here, but it's clearly in the base game that some enemies are going to miss turns. Where it is in the code I have no idea, but it clearly is there since enemies do miss turns in the base game, and I personally notice it more with relatively lower level enemies.
I suppose it's possible that the tutorial NPC has incorrect info, but then that's on Remtairy and the missed turns are a bug, but the tutorial message makes me think it's intentional.
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