Hi champion-setting,
I set up some joints, animated those, and then used the PoseMorph with the Magnet. I felt all settings were the same as when using the Magnet, except I went from Edit to Animate afterwards.
Let me know if that causes also problems.
I used 2024.4
You could also explore a copy of the model and use it as an external source for the Magnet/Meshwork.
All the best