Kain has far more important powers and abilities than Immolate. Lightning, a wide-range lightning attack would be impossible for Dante to dodge. Kinetic Shackles would allow Kain to chain Dante with pure force of mind. Also, the Soul Reaver doesn't really need to pierce Dante. One or two slashes are fatal to any creature, especially a half-demon. Dante wouldn't stand a chance in a close-quarters confrontation or in a long-distance battle due to Kain's amazing physical and mental strength.
Still, I'm no Dante expert. I'm sure someone can formulate a good strategy for him...that I could destroy.