Challenge Incursion Breaker achievement has the numbers the wrong way around. You start with III, then get II and finally I. Shows 5 points instead of 15 after completing them all.

Give No Quarter requires Challenge Cave Delver III.

However, I have only completed Challenge Cave Delver I. For some reason the game lists that I have done Challenge Cave Delver II. So which is it?

I have completed all of those on Vestige difficulty if that makes any difference.