Cover green lentils with boiling water in a saucepan. Allow to soak for 1 hour.
Whisk peanut butter, rice vinegar, water, lemongrass paste, tamari, sugar, oil, lime zest and juice, green curry paste, ginger paste, and garlic paste in a bowl; set dressing aside.
Drain lentils. Fill saucepan with enough fresh water so lentils are covered by 1 inch. Bring to a boil over medium-high heat. Reduce heat and simmer until lentils are cooked through but not mushy, about 20 minutes.
Meanwhile, put kamut grains in a saucepan and fill with enough water to cover by 1 inch. Bring to a boil over medium-high heat, reduce heat, and simmer until soft, about 10 minutes. Drain kamut and lentils and let cool.
Combine cooled lentils and kamut grains in a bowl and toss until mixed well. Add tomatoes and radicchio. Drizzle dressing over salad and toss to coat. Allow to rest at least 10 minutes before serving. Top with chopped cilantro.