Heat grill to medium-high.
In a bowl, toss the chicken, garlic, thyme, 1 tablespoon of the oil, and ½ teaspoon each salt and pepper. Thread the chicken on the skewers.
Grill the chicken and corn, turning occasionally, until the chicken is cooked through and the corn is charred, 7 to 10 minutes for both.
In a bowl, toss the tomatoes, scallions, orange zest, remaining tablespoon of oil, ¾ teaspoon salt, and ¼ teaspoon pepper.
Serve the tomato salad with the chicken and corn.