Brush pork tenderloin with canola oil; sprinkle with 1/4 teaspoon salt. Grill on medium-high, covered, 10 minutes, turning once .
Whisk hot sauce with brown sugar and garlic cloves. Coat plums, with oil. Grill, cut sides down, 3 to 5 minutes, covered, turning once.
Toss plums with cabbage, 2 teaspoons oil, and salt to taste; transfer to platter.
Brush pork generously with hot-sauce mixture; grill 6 to 8 minutes more or until cooked through, brushing and turning. Slice pork; serve over plums and cabbage.