Great post- thanks for the stats- I had no idea that some asteroids were so dense in these metals. Perhaps build a space elevator and use the asteroid as the space counter weight? But then of course your couldn't mine it all away- or perhaps before fully mined you attach it to a newly docked asteroid- wash, rinse, and repeat?
We might use the extra bits as counter weight if it is needed, but I wouldn't trust asteroids that close to Earth tbh