Pickapeppa Chicken and Pineapple Kebabs

Name: Pickapeppa Chicken and Pineapple Kebabs
Ingredients: 1/3 cup cider vinegar; 1/4 cup dark rum; 3 tablespoons firmly packed dark brown sugar; 1 bunch scallions (white and green parts), roughly chopped; 4 cloves garlic, chopped; 1 Scotch bonnet chile, stemmed, seeded, and minced; 2 tablespoons Pickapeppa sauce; 1 tablespoon freshly grated peeled ginger; 1 tablespoon ground allspice; 1/4 teaspoon pumpkin pie spice; 3 tablespoons vegetable oil; 4 boneless, skinless chicken breast halves (about 1 1/4 pounds), cut into large cubes; 1 bunch scallions (white and green parts), cut into 2-inch pieces; 1/2 fresh pineapple, peeled, cored, and cubed; Kosher salt