Left rear wheel wobbling

If the wheel is wobbling then more than likely the knuckle is bent or at least where the bottom of the strut goes into the top of the knuckle.

The other major thing it could be is the lower control arm is bent. These are not the strongest components by design. They are meant to be the weakest point so that it collapses rather than them penetrating the body or other components in the even of an accident.

I would check these two and then if nothing else is found bent, you can have an alignment performed because there are adjustments for the rear suspension. Let me if you have questions.