Better news . . . I managed to free up the anchor swivel by going at it with the breaker bar a bit more. Then I worked some grease into the pivot pin and that made a difference.
this is the larger of the SeaDog Stainless Steel Swivels as it can go up to 3/8" chain, etc. I needed the large swivel as the anchor shank is 11/16" . . . almost 3/4" and the swivels with the 5/8" openings just weren't making it.
I heat shocked the swivel for a while with boiling and ice cold water, then I went after it again with the breaker bar, etc.
Here are a few pics and a video that I took while working the swivel into submission.
Anchor with swivel in the workmate and using the breaker bar
Once I got the the swivel to move somewhat freely, I worked some grease into the pivot bolt area and then hooked up the drill to it using a piece of hose as a coupler.
Here is a quick video of working in the swivel . . .
I think it is going to be OK after all . . . but there was definitely something wrong with it from the get-go.