doesnt count as a kill sirSolo'd the 6 paths of Pain.
He can kill anyone he wants with the exception of the Juubi.
Pretty sure he killed kakuzo .... They commented on how the effect nearly destroyed narutos arm beyond repair from just delivering the attack...
It is safe to assume that kakuzu's body was beyond repair due to the duration of exposure to the effect...
Maybe Kakashi finished him off so he would die quicker but I would assume he would have died anyways.
Or let me put it this way:
If I were to shoot you in the stomach and just left you... You would die within ten minutes ...
If however someone were to step in and finish you off douring those ten minutes ... Would you seriusly put the kill on that guy's list instead of mine?
killed Kakuzu.
also killed 3rd Raikage, again (since he died before already) xD
also killed all 6 Pain's bodies (they were dead bodies, but who cares?) xD
also killed a bunch Zetzus
there might be more...