Interesting story. When I was in 2nd grade, we had a park ranger or someone come to the school to show us some animals we could encounter in the desert, including a gila monster. At one point he prodded it with a large piece of sheet metal and it chompped on it. The bite was strong enough that the Ranger could pick up the sheet metal and the gila monster did not fall off. He swung it around and it still did not fall off. He set it back in it's cage and it only let go when he put in a dead rabbit in the cage for it to eat and he showed us the sheet metal afterward. You could see the teeth marks in the sheet metal.