The pictures make the trim look to be in pretty poor shape. I, too, would be pretty frustrated with them at this point. I've had a LOT of warranty work done at Chrysler dealers, and they were generally pretty good at it. I ended up fixing a lot of stuff myself, though, because of the hassle of constantly carrying our van back in...
Which made me think...that piece of trim can't be more than 20 or 30 bucks, right?
Then I remembered your original post. Two plastic trim pieces are SIX HUNDRED DOLLARS? What's the other trim piece involved here. SIX HUNDRED DOLLARS? Are they out of their minds?