Brine the chicken: Combine 2 quarts water, the salt and sugar in a medium saucepan; bring to a boil and cook until the salt and sugar dissolve, about 5 minutes. Remove from the heat and add the garlic, thyme, cinnamon, allspice, peppercorns and Scotch bonnet. Let the brine cool completely. Add the chicken wings to the brine, cover and refrigerate at least 4 hours and up to 8 hours. Remove the wings from the brine, rinse well with cold water and pat dry. Put the wings on a baking rack set over a baking sheet and put in the refrigerator to dry, at least 1 hour and up to 8 hours. Meanwhile, soak 2 cups pimento or apple wood chips in water at least 30 minutes.
Make the glaze: Heat the oil in a small saucepan over medium-high heat. Add the ginger and cook until soft, about 2 minutes. Pour in the orange juice and 1/2 cup water and bring to a simmer. Add the tamarind, ketchup and honey and cook, stirring occasionally, 5 minutes. Remove from the heat, whisk in the vinegar and Sriracha, and season with salt and pepper. Let cool slightly. Heat your grill to medium for indirect grilling. Add the drained wood chips to the coals in a charcoal grill or put them in the smoker box of a gas grill. Close the grill cover and let smoke build, 10 minutes. Add the wings to the grill directly over the heat source, close the lid and grill until golden brown on both sides, 10 to 15 minutes per side. Transfer to the cooler side of the grill (indirect heat), cover the grill and continue cooking until the wings are cooked through, about 15 minutes. Put the wings in a large bowl. Add the honey-tamarind glaze and toss to coat. Season with salt, transfer to plates and garnish with scallions.