A few tips to help make your animation easier. Might not be perfect, but I think it's a good start.
I noticed that doing this same process in Maya 2022 doesn't work the same. I'm guessing it's a bug that Autodesk will hopefully fix on the next update.
Rig = Symmetro by Kiel Figgins
http://3dfiggins.com/Store/#FreeStuff
Spear by DefVader
https://sketchfab.com/3d-models/spear-6e48245075af4dd792a5449007407585
cheers