Uncontained engine failure
I worry about the use of the term uncontained engine failure because it suggests that not only did the rotating machinery fail in some way but also that the containment was inadequate (because it failed). I suspect that total containment is impossible (because of weight considerations) but that some sensible design point is chosen by risk analysis.
Therefore, there will always be situations in which the design case or the certification standard is exceeded by an actual occurrence. I agree that the damaged wing does suggest that at least one piece of machinery was not contained but it does not follow that there was anything amiss with the containment system.
Unless a design, manufacturing or maintenance error exists, the containment will have performed as designed (if not as expected) even if it was penetrated.