Getting down from Earth orbit is tough because you must shed all that orbital velocity. If you started getting to Earth not from orbit, but from a freefall state, you don’t need to go from 7 miles per second to zero, at which point you can simply fall, like Baumgartner did.
So once you get your chunk of metal, you can fashion a simple wing structure out of slag and fly that down like a glider, you can crash it because it’s just asteroid slag with a core of heavy metal. If it buries itself 10 meters deep at your landing site, no problem, it’s a lump of platinum or palladium or gold.
Where are you going to do this fashioning, I think this is more probilmatical than you think!