Thanks Omar, Wayne!
I think I actually saved things over the file I was using as an example when I made Rivet local, per Shawn’s suggestion on the animation Discord. As a local object it was working fine.
Up until making things local everything I did was pretty much the same as you described until hitting F3. Instead of F3 I clicked on the four way arrow then went to object->relations->Library Override. Maybe clicking on the arrow is what broke things, I’m not certain.
At any rate, following your directions things worked well. Thanks!
Edit: No, I was mistaken. It was acting like it was before. Taking the animation data as I was manipulating things in the viewport, but not actually saving that animation data.
I think I finally got it. Wish I could paste images here. . .