So yeah I can see why you choose not to take their word when they say that they have evidence.
But trust me bro :-)
But seriously now, I don't really understand why it would be shocking to discover Hamas is operating from hospitals, mosques and schools. They are fighting a war and will do anything they can to gain an advantage.
It's very convenient to deploy your base under a hospital, for so many seasons, that I really don't understand why people find it hard to believe...