Neiji avoided the attack. As was explain in the entire battle, Kidoumaru has been trying to hit Neiji's blind spot, but he always fails to do so. Even in the very last page of the last chapter, Kidoumaru's attack did not, I repeat did not connect in Neiji's blind spot. Neiji's blind spot was shown to be in his back, a spot on his spinal cord below his neck(about 10cmish)

So he is difinately not going to die. Whats more, Neiji, figure out that kidoumaru has been using a string attached to his arrow. And Neiji is going to use the string to either track kidoumaru, or send a jolt of chakra(like electricity) to fry kidoumaru in his track. And then Neiji will have fried spider for dinner to replenish his chakra/stamina before whatever next happens.