124 rear bearing help 87 300E

I have a rear noise that sounds like a wheel bearing. I took it to the independent to have it checked out and he said the left rear was loose. I told him to replace the bearing and when he got it apart it everything looked ok. The noise has been getting worse or I’m just aware of it more. (About 5-6K )He said the hub was bad . Has anyone replaced rear wheel bearings? The outer race was still on the hub but the inner race was apart. Where the inner race is pressed to the hub… the hub has a grove… not flat and smooth like you would expect. It could be the casting because the old bearing does not have any scoring. I don’t want to replace the hub for 130.00 if it is not necessary. Is anyone experienced with rear bearing and understand what I’m talking about. Your input would be appreciated