Nobody believes what Israel are saying, they just pretend that they do. At this point everybody knows that Israel break International law every single day, the ICJ were clear about that, clear that Israel systematically discriminate against Palestinians and deny them basic human rights. The ICJ even mentioned Israels lying saying that they use deliberate efforts to rewrite the rules of international humanitarian law, using it as “humanitarian camouflage”
Who in their right mind would believe a country who persecutes Palestinians on a daily basis for decades and lies about it. The answer is obvious, no one. We have Palestinians who are being systematically persecuted, against International law, now being killed in large numbers by the people who persecute them. It doesn't take any kind of genius to work out what is happening, even if you can't work it out yourself there are lots and lots of experts who have worked it out for us.