When Narayani sena was given to Duryodhana, Was shri krishna's son samba was the head of that army?
If yes, then in-spite of being a son of lord Krishna, did Samba go against him in Mahabharatha war?
How did he die?
There is no reference found of Samba participating in the great war.
Kritavarma was the head of Narayani sena and not Krishna's son Samba.
In the left foot, O monarch, was stationed Kritavarma accompanied by the Narayana troops, and those invincible warriors, the gopalas. In the right foot, O king, was Gotama's son of prowess incapable of being baffled, surrounded by those mighty bowmen viz., the Trigartas and by the Southerners. In the left hind-foot was stationed Shalya with a large force raised in the country of Madras. In the right (hind-foot), O monarch, was Sushena of true vows, surrounded by a 1,000 cars and 300 elephants. In the tail were the two royal brothers of mighty energy, viz., Citra and Citrasena surrounded by a large force. [Karna Parva]
In fact after 36 years from the war, Samba was killed in an internal fight among the Yadava-s clan which was intoxicated with power and wine. Other sons of Krishna were also killed:
Knowing that the hour of destruction had come, the mighty-armed Keshava stood there, eyeing everything. Indeed, the slayer of Madhu stood, raising a bolt of iron formed of a blade of grass. Beholding that Samva was slain, as also Charudeshna and Pradyumna and Aniruddha, Madhava became filled with rage. [Mausala Parva]