honest question: if a golf cart sized spacecraft ejected 1M Kg out of this asteroid, if it had hypothetically hit the earth's atmosphere, would it have broken up easily?
If the impact speed were ~30 km/s [1], breaking it up in the atmosphere through friction would create about...
E = MV^2/2 = 3.87 10^18 joules.
For contrast, the energy released by the Tsar bomba was 2.45 * 10^17 joules. The Tunguska meteor impact was something on the order of ~1 * 10^17 joules.
Even if much of the energy dissipates in the upper atmosphere, and does so over multiple seconds, I'd say that anyone within ~150 miles of the point of 'impact' will likely have a very, very, very bad day.
[1] Which is a pretty bad case. The Chelyabinsk meteor was traveling at ~18 km/s - a 30 km/s impact would be close to a 'head-on' collision.
Anyone within one or two hundred miles of the impact site would have an incredibly bad day, but it's not civilization-ending.
The Chelyabinsk meteor, FYI, weighed ~12M KG.