Combine the pork, orange juice concentrate, and 1/4 cup of the soy sauce in a large ziplock plastic bag. Seal and marinate in the refrigerator at least 12 hours or up to 2 days.
Combine the orange marmalade, scallions, chicken broth, Cajun seasoning, hot sauce, and remaining 1/2 teaspoon soy sauce in a small saucepan over medium-high heat. Bring to a boil, stirring occasionally; reduce the heat to medium low, and simmer stirring occasionally, until thickened and reduced to 1 cup, about 15 minutes. Remove 1/4 cup of the sauce for basting; reserve the remaining sauce for serving.
Preheat the oven to 425 degrees. Remove the pork from the marinade; discard the marinade. Sprinkle the pork with salt. Heat in the oil in a large ovenproof skillet over medium-high. Add the pork to the skillet; cook 4 minutes. Turn and cook about 1 minute. Baste the pork with 2 tablespoons of the sauce. Cover the skillet with foil; bake in the preheated oven for 5 minutes or until a thermometer registers 145 degrees, about 5 minutes. Place the pork in a cutting board; let stand about 10 minutes. Cut the pork across the rain into thin slices. Serve with the reserved 1/2 cup sauce. Garnish and serve with the reserved 1/2 cup sauce. Garnish and serve with rice if desired.