They do include the victims of their own terror. If you look at the lists made by the PA, you will see that nobody dies because they blow themselves up, for instance. You can compare those lists with those elaborated by the Israelis. (In the lists the cause of the death is also mentioned). I have also read that the "Pals" include people who die from illness or any other cause.
from the article: Demons in the skies of the Gaza Strip