It’s very telling that the media began insinuating (or labeling outright) Representatives Omar and Tlaib as being antisemitic for criticizing Israel’s response, but when Sanders says the same thing, and even more, they don’t.
If it’s not antisemitic for a Jewish person to say, it’s not antisemitic for someone else to. No one is immune from criticism that would otherwise be valid, simply because of who is giving it.
No one is seriously questioning the authenticity of this attack, though I would not be surprised if Bibi knew of it (since, you know, they were literally told about it beforehand) and allowed it to happen to both avoid his legal troubles and to give his ultranationalist party and military a pretense for driving out or killing Palestinians.
Pearl Harbor and 9/11 weren’t fake either, and both were used to excuse atrocities too.