Seems like it’s honing in on a collision with Earth over time. Wonder if there are any realistic factors in nature that could nudge it one way or the other.
Sure there are: a near-miss with any of the planets, asteroids or comets. But, especially Saturn and Jupiter, where the misses don't have to be especially near in order to nudge the orbit significantly.
Note, too, that although the orbits of the major planets and many asteroids are well-known (and, therefore, predictable well into the future), there remain as-yet undiscovered asteroids, plutoids and comets, and a near-miss with one of those could go both unpredicted and unnoticed.