Trim the pork loin with a sharp knife to remove any fat and sinews. Holding the knife horizontally, carefully cut through the loin lengthwise, stopping just before cutting completely through, so it opens like a book with even thickness.
Place the Camembert slices in the center of the opened pork. Add the 3 tablespoons of jarred cranberries on top.
Roll the pork tightly and secure with kitchen string or skewers. Rub the outside thoroughly with the raspberry mustard rub.
Heat a grill to medium temperature. Place the pork roll on the cooler side (away from direct flames or coals). Cook for 35-45 minutes, turning occasionally, until the internal temperature reaches 63 °C / 145 °F at the thickest part.