This is an interesting question but would likely have an infinitely complicated answer.
A myriad of other factors - social, socioeconomic, genetic, cultural, psychological - have to be somewhat primed in order for a suicide to trigger a series of copycat suicides. It was noted in the '90s that even Kurt Cobain's death did not particularly lead to many copycat suicides.
And yet, in a suburb where I used to live, there was a number of schoolchildren who CTB-ed in a row from the same school; the suburb happened to be quite far from the city and all would have the common theme of parents who were too busy commuting to be emotionally available.