Death is not always from G-d?

 Kuzari (05:20) David laid down three causes of death, viz. 'God may slay him,' i.e. divine cause; 'Or his day shall come to die,' i.e. natural cause; 'Or he shall descend into battle and perish,' i.e. accidental cause. He omits the fourth possibility, viz. suicide, because no rational being seeks death voluntarily. If Saul killed himself, it was not to seek death, but to escape torture and derision. 

Sefer HaIkkarim (4:21): This death that You have decreed upon me can only be one of three types. 1) Punishment for sin 2) Decree of the constellations 3) Natural death. These three types of limits to one’s life are mentioned by Dovid (Shmuel 1 26:10)…. As Divine punishment, natural death or premature accidental death which happens even without sin as the result of the stars or general decree. … Dovid did not mention suicide since no one freely chooses to die…. 

Kuzari (5:20): … The Prime Will is manifest when the Divine Presence is amongst the Jews. However after the destruction of the Temple it became doubtful - except in the hearts of those who have faith - whether specific events were the result of the direct command of G d or the Heavenly spheres or were accidents. There is no definitive way to resolve this issue. Nonetheless it is best to attribute everything that happens to G d, especially major things such as death, victory, war, success and bad fortune.

Menoras HaMeor (#298): When a person has a calamity happen to him he should not think that it was just by chance. Because whoever mistakenly believes that is punished measure for measure and is deserted to chance without any protection… This is a very great punishment because there are many opportunities for accidents to happen and if one is deserted by Heaven he has no protection at all… This verse that says that evil doesn’t descend from Heaven is because a sinner doesn’t need to be harmed from Heaven it is sufficient that his protection is removed and then he vulnerable to accidents and suffering since there is no suffering without sin… Therefore a person must believe with solid faith that G d knows the secret matters and He is the true judge and judges the entire world …

Shomer Emunim (2:81) Nothing occurs by accident, without intention and Divine Providence. This is learned out from the verse; ‘And I will walk with you in chance (be’keri).’ From this we see that even the state of apparent ‘chance’ is actually Providence. “But that does not apply to the non-human species...whether this ant will be trodden upon or saved. There is no special Providence for animals and certainly not for plants and minerals, as they are governed by species and not individuals. Whatever occurs to individual animals, plants and objects is purely by chance, and not by Divine Decree – unless it is ultimately connected to humankind