prijedor

Friend of mine just picked up 2001 S4 Avant 95k.
Car was checked by local Audi specialist and no issues.
Previous owner had rear drivers side wheel bearing replaced in March by another shop.
When we picked up a car I was driving behind him and noticed that left rear wheel is wobbly .
Wheel was put on balancer machine, no problem there.
My friend brought a car to mechanic and was told that axle hub is the reason.
I was thinking that is possible that hub was damaged during wheel bearing replacement.
Anyone had similar experience?
So far looks like new hub is dealer only option.$350-$370 depending on vin number.
Does anyone have part number for rear axle hub assembly?

Thank you.