"Why would a jewish news site know all this first?"
First, I have to say its not exactly a "news" site. While their accuracy seems good to me, and I beleive they are being as accurate as they can be, the site includes speculation.
Secondly, while the Israelis are indeed "Jewish", its a bit naive to think they focus on "Jewish" affairs and hence don't know much about "Moslems". Their very survival depends on the highest possible level of knowlege of all things Arab.
Sorry, they may care about what happens in Arab lands, but why would Arabs talk to them first and not, say a more neutral or pro-Palestinian source?