For the rotisserie lamb with pomegranate and mint: Sprinkle both sides of the lamb with salt and pepper. Roll the lamb and tie with twine. Cut small slits over the entire lamb, using a paring knife. Fill each slit with a slice of the garlic. Put the lamb into a large plastic resealable bag.
Whisk the pomegranate juice, wine, olive oil, oregano, rosemary, onions, bay leaves and lemon juice in a bowl and sprinkle with salt and pepper. Pour the marinade over the lamb, in the bag. Press the air out of the bag and seal tightly. Place the bag into a large bowl. Refrigerate the lamb for at least 4 hours and up to 24 hours, turning the bag a few times during that time.
Remove the lamb from the refrigerator 30 minutes before cooking. Preheat the grill to medium-hot heat.
Whisk the pomegranate molasses, mint, mustard and lemon juice in a medium bowl and sprinkle with salt and pepper.
Skewer the lamb onto the rotisserie and grill until a meat thermometer registers 135 degrees F for medium doneness, 1 1/2 hours to 1 3/4 hours. Begin brushing the lamb with the pomegranate molasses mixture after about 45 minutes of grilling.
Meanwhile for the Greek slaw: Whisk together the lemon juice, olive oil, dill, honey and garlic in a large bowl. Sprinkle with salt and pepper. Add the red and green cabbage, carrot and feta. Toss to combine. Cover the slaw and refrigerate for at least 30 minutes before serving.
Transfer the lamb to a cutting board and loosely tent with foil. Wait 15 minutes before slicing.
While the lamb is resting, brush the tomatoes with canola oil and sprinkle with salt and pepper. Grill the tomatoes until they are charred on both sides and just soft, about 4 minutes.
Slice the lamb. Lay the warm pita breads on a large platter. Top with sliced lamb, grilled tomatoes and the Greek slaw. Squeeze the lemons over the top and serve.