In a small bowl combine the rub ingredients. Lightly coat the chicken thighs on both sides with oil and season evenly with the rub.
Prepare the grill for direct and indirect cooking over medium-high heat (400° to 500°F).
Brush the cooking grates clean. Grill the chicken over direct medium-high heat, with the lid closed, until browned but not fully cooked, about 4 minutes, turning once. Remove from the grill and let rest until cool enough to handle.
Grill the corn and chile peppers over direct medium-high heat, with the lid closed, until the corn is golden and the peppers are blackened on all sides, 10 to 15 minutes, turning several times. At the same time, grill the tomatoes over direct medium-high heat until lightly marked and tender, 5 to 8 minutes, turning once or twice. Remove the vegetables from the grill and let rest until cool enough to handle.
Cut the chicken into ½-inch pieces. Remove the corn kernels from the cobs. Peel and discard the skin from the poblano chiles, remove the seeds, and cut into ¼-inch dice. Remove and discard any loose skin from the jalapeños, and then finely chop. Remove and discard any loose skin from the tomato and cut into ¼-inch dice.
In a large saucepan combine the broth, chicken, corn, chile peppers, tomatoes, half of the cilantro, and the oregano. Bring to a simmer and cook until the flavors come together, about 15 minutes.
Place a small handful of tortilla chips into each soup bowl and ladle the soup on top. Serve hot with the remaining cilantro, lime wedges, and sour cream.