Kenmore 700 Model 110.29732800 Loud grinding noise during agitation but spins & drains fine

Brand: Kenmore
Model Number: 110.29732800
Main Symptom: Loud grinding noise while agitating
What happens & when: When agitating a loud grinding noise is heard.

Error Code (if any): none–too old
Parts or tests already tried: Replaced dogs and took top of agitator off. Cleaned everything but can’t get bottom half of agitator off to check or clean that.
Photos / video link: https://drive.google.com/file/d/1i2SJ1QN8FzHK1YM2PxbjN8uVhfy10lpc/view?usp=drive_link

You will want to check the dogs on the agitator as this would be the most likely cause for the grinding noise.

Already changed dogs (they were gone!) and bolt (all rusty) in agitator. Still doing the grinding sound during agitation. No issue with spin or drain cycles. Can’t get the bottom half of the agitator off to check that but sadly have had several people say it’s the transmission?? Thinking I may have something stuck underneath the agitator as I had to pull several items partially stuck underneath out several months ago (hubby admittedly overfills!) This could have progressed from that incident but it seemed to be working fine. The agitator was turning both ways and needed the dogs. Not sure how long it was doing that. Would love to get that bottom half of the agitator out!

Taking off the lower agitator and checking the splines would be a good choice. If the splines are bad on the agitator base then it could cause the grinding noise. I know getting the base off can be a pain but if you use a 2 x 4 and ratchet straps you may be able to use the leverage to remove it.