DO NOT PANIC.

This is a common issue with updated models that have a bone change. In this case, the hands were updated. First off, don't worry, your work isn't lost as you've got two choices if the "Reattach to Model" function under utilities doesn't work:

1.) Download the old versions of the models here[mega.nz] or {LINK REMOVED}here and override them in your workshop folder.

2.) The bones on your animation or poster for the Inkling girl are preserved--only the mesh is garbled. You can spawn in the new model, parent the bones to the old one as if it were a clothes item, zero their locations to the old bones, and hide (NOT DELETE) the old model. You'll have to go back and fix the hands since the fingers were updated to be more user-friendly and will look bent-outta-shape otherwise, but your work will be mostly restored.