Hi Kent,

Are you driving it now, and it's making funky noises?
Does it snap and pop when turning?
Maybe it's not fully engaged?
If so you might find out by needing a tow.
Make a recording of the noise and post it.

Is it the original transmission?
Was the drive axle making abnormal sounds before they did anything?
Why didn't they compare drive axles before installation?
Did they bill you for a new drive axle?
If they used a bad part they should replace it.

I don't see a bad ball joint wrecking a drive axle.
Did you get your original drive axle back to see what was wrong with it?

I'd get another mechanic to look at your issue.

Bill