The kneeling soldier jump up a little bit, when died(and partially when get hit).
I think it's caused the wrong initialization of the ragdoll. It's looks like that there is a tension in his legs when he die.
Because of this tension the character to kick with his legs and jump off.
E.g: https://youtu.be/xVxnNYA9It4?t=6m21s
Slow motion: https://youtu.be/j62WeTY0uMI {F26835}