Combine the first 8 ingredients in a medium bowl. Cover and refrigerate salsa until needed. Preheat barbecue or indoor grill to medium-high. Brush the sablefish with the 2 Tbsp. oil; season with salt and pepper. Lightly oil the bars of the grill. Grill the fish 3 to 4 minutes per side, or until just cooked through. Plate the fish, top with salsa, and serve.