That is a serious feud you’ve got there! There used to be dog poop wars in the neighborhood we lived in in the city-usually a couple of times a year, but nothing like what you are describing. The main offenders were a couple who had what my daughter called a gaggle of yappy Chihuahuas.
We both live across the street from the park...NO ONE will go there or even walk down the street. People I meet while out walking, when they find out where I live they ALL tell me they won’t go down our street anymore. They are too scared of the dogs. It’s lonely over here.