How does Ralph contribute to the death of Piggy?

Ralph does not mean to cause Piggy harm. I think Piggy was a target regardless of Ralph being on the island. Ralph knew the situation was at a boiling point when he and Piggy went to Castle Rock in chapter 11. Ralph gets into a fight with Jack, which was bound to happen. Whenever there is tension, the all the boys find relief by humiliating Piggy. The savages (most of the boys), however, are well past humiliation. Roger, being a sociopath, launches a big rock from a cliff, which kills Piggy. Ralph's visit escalated the pent up violence in the boys and Piggy is always the first target.