Earlier quoted context omitted.
This is absolutely trivial as long as any fixed ground objects are visible in a camera and does not at all require some sub-pixel precision.
It's trivial to draw a line between some fixed points and extrapolate back to an origin if there's no external forces acting on the asteroid. But there is - planetary gravity, the moon, potentially the sun heating one side of it, atmospheric wind, weather, etc make a big difference. That makes it harder.
Also, a typical consumer camera is going to struggle (even with the best analysis!) to have visual accuracy within even a few degrees of true (due to everything from high compression ratios in post processing to shitty optical properties in the actual camera) and that makes a probability cone that is pretty large.
Still better than nothing, though!