The entire situation is more complicated than how you have presented it.
Speculation such as this does not really serve any purpose - and "shouting out" the same information again without any substantiation does not increase its validity.
Also - not to single anyone out with this - but this is not a good subject for a flame war... We need to be considerate of the many wonderful people who have welcomed us to MECCA year after year.
I know a few people at the Fairfax plant. A couple are "in the loop" when the efficiency of a plant comes into question. Simply put, the way GM is structured a production level of 30-40,000 units per year is not profitable at lower price points. Corvette makes enough money to justify its existence because the costs are covered in the higher pricing. Kappa were at least as labor intensive that the number of hands and hours killed the profits. Kappas were always "halo" cars and as such served their purpose, were due to "go away" after the 2010 model run, and even if there was going to be a Kappa II there was no guarantee where it would have been built so Wilmington's "life after Kappa" was always a question.
As for the "flaming" assertion .... bull. The people at Wilmington built the car. They didn't design it, nor did they create the assembly methodology. Cars are only as good as the design and components. What is often not recognized is the assembly line and how it is used is "designed" as well. If the design of the car, choice of components, and the design of the assembly line/methods don't mesh well, you have water leak, diff issue, crappy door handles, sagging seats, etc. A lot of the responsibility for these problems can't be put on the assembly line workers, so if people are critical of some issues with Kappas there is no reason to assume that they are pointed at line workers at Wilmington.
Bottom line, a low production, high content, labor intensive, and modestly priced car being built at a high cost facility with expensive labor is the perfect storm for no profits, ESPECIALLY with a fairly high warranty claim rate. My assertion of "poorly built" is not too far off target because it was almost predictable (reread first two paragraphs for reference) given all that was involved. As a former manager once shared with me, "you are perfectly positioned for the results you have obtained".