If the news of Israel's Prime Minister is to be true, which I doubt, we would have by now, heard of different countries presidents sending their condolences to Israel about the death of their Prime Minister. And up till this moment, I haven't heard of any condolences, coming from any of the world presidency, which is unusual.
Does that mean anything, or does the other country's President don't wants to send their condolences across to Israel? Having this thought at heart will give you a clue that Israel's Prime Minister is not dead cause if he were, you would have heard of some countries president sympathizing Israel citizens about the death of their leader
It would be realistic to assume Netanyahu is simply avoiding to appear in public so he cannot be easily targeted by agents of Hamas and Iran.
It is not a secret there are powerful people out there who are seeking to assassinate him, in the same manner his brother as killed recently by an Iranian rocket.
I don't believe he is actually dead, that Israel would need to appoint a by prime minister in order to continue the chain of command, according to their constitution and laws.