[Getready]

Could there be a heretofore unseen asteroid careening on a collision course with this asteroid that “billiard balls” it on a new path towards earth?

[Red Badger]

In space, no one can hear you careen............

[Paul R.]

No collision is necessary. A gravitational nudge, if it occurred, say, 2 years “out”, could easily do the trick.

[alexander_busek]

Could there be a heretofore unseen asteroid careening on a collision course with this asteroid that “billiard balls” it on a new path towards earth?

You are apparently thinking of something like this:

But it's more like this:

Regards,