No, based on DNA, I don't think Cocco is where the link is going to happen, but somewhere on the Lamparelli line. However, I tried looking at records yesterday (slow as molasses for me!) and couldn't find another child for Giuseppe Lamparelli and Maria T Gallo. It could also be one of the children of Antonio Lamparelli/Teresa Bruno who married a Giorgio. The Coccos are too close to work for this scenario unless there's another marriage. For instance if Maria Rosanna Lamparelli had another marriage.
I didn't need more children for Gaetano and Rose Brancato because the amount of shared DNA on this line tells me I need to look further back in the tree. In the case for this line, the Giorgio couple were the important part of the tree. Knowing that now, I don't need any more on this tree. It's all about how one tree links to another through marriage or parents. That's where the adoptee is related in the tree.
When there aren't high DNA matches to work with, a lot of this is guess work until the pieces start to fall in place.