I dunno how they arrived at 30,000 mph, but it’s quite credible. A object falling from the Ort cloud to the surface of earth will be traveling about 44 km/sec (100,000 mph), most of the acceleration being provided by the sun’s gravity. The atmosphere will slow it down some...
Credible? Objects traveling at 30,000 mph don't "bounce off" of anything, let alone a human hand. They also don't hit anything of substance and remain intact. Objects traveling at 30,000 mph explode when they hit solid object, like boys or the ground. At most, I would surmise that this meteorite was traveling at about 600 feet per second, or a little under 200 mph when it hit him. Otherwise it would have pierced the skin.