Let's do the math, because dollars make no sense when talking about a metal: $10,000,000,000,000,000,000 dollar and $55,000,000 per tons. That's 182 billion tons.
Now let's see what
National Geographic has to say:
one geoscientist calculated that there are 1.6 quadrillion tons of gold in the core—that’s enough to gild the entire surface of the planet half-a-meter (1.5 feet) thick
Why bother with an asteroid, if the earth's core holds 8800 times more gold?
Probably unimaginable pressures and heat not to mention radiation makes it unobtainable compared to space