What is wrong with this tire?

Is the wear on the inside or outside? Can you feel a sharpness on the tread edges when you run your hand across the tread face?

 

Normally, when the rears are out of alignment by a considerable amount they will scoot the steer tires sideways causing heavy wear on the inside of one steer tire and the outside of the other steer tire. The wear you show in pictures and describe would make me want to look for too much positive camber on your steer axle, especially the left wheel. I would also want to align the drives.

 

Proper way is remove wheel and use a dial indicator.

But try finding someone who does things proper in this industry!