Admiral Top Load Washer ATW4475VQO won't agitate

Washer Repair
1

Brand:Admiral
Model Number: ATW4475VQO
Main Symptom:Bottom of agitator doesn’t go back and forth
What happens & when:Bottom of Agitator goes clockwise in spinning motion wrapping cloths aroung the agitator. When the agitator is off the splined shaft, the shaft moves back and forth as it should, The splines on the shaft look fine and it appears that the inside of the agitator does have matching splines.

Error Code (if any):None
Parts or tests already tried: I replaced the dogs in the top of the 2-part agitator and the top seems to work correctly
Photos / video link:

2

This issue sounds like the agitator would be the issue due to the splines being stripped out.