My small NJ town has its own school district, containing a single K-8 school. Yet it has both a superintendent and a principal.
Grades 9-12 feed into a regional high school, which also has its own school district containing just that school. It also has its own superintendent and principal.
I don't think "redundant" is a strong word for this situation.
Sorry but I'm not spending an hour doing math on employee counts just to satisfy an HN commenter. There's no universe where it is sane and reasonable to have 4 separate highly-paid school superintendents in a 3-town area (towns feeding into the regional HS) with total population of only 25k, especially as these schools don't even rank particularly well.
And that's not even accounting for the principals. Think of it this way: if a country's navy has only a single boat, does it really need both an admiral and a captain?
NJ has effectively a publicly operated system of private schools where the tuition is the tax burden.