Heat a small saucepan over medium heat and cook the shrimp shells, in the cup of water with 1/4 teaspoon salt added, until the liquid is reduced by half, about 5 to 6 minutes.
Place tomato in a large bowl; strain broth from boiled shrimp shells into bowl with tomatoes.
Cook sausage meat in a Dutch oven, over medium high heat, until browned and some of the fat is rendered, about 6 minutes; use a wooden spoon to stir and break up the meat while cooking.
Add the onion, garlic, chili pepper, 1 teaspoon salt, black pepper, paprika, and crushed red pepper flakes to the sausage and mix well.
Cook until the onion softens, about 6 minutes.
Add chopped tomatoes and shrimp broth, increase heat to high, and cook until tomatoes break down, about 6 minutes more.
Remove from heat, stir in shrimp and vinegar; cover and let stand until the shrimp cooks through, about 3 minutes.