The simple 4% figure distorts the demographics involved. Illegals form a greater proportion of the lower economic levels where a higher proportion of violent deaths occur. They are also a greater proportion in population centers where again higher proportion of violent deaths occur.
I have not argued that there will be strict proportionality and that the figure would be higher than the citizenry for murders but not for automobile accidents due to the lower auto ownership rates for the poor. So that might cancel out to some extent. Nor do I believe that the large urban areas have a higher death rate for auto accidents.