Hello Nate! Is a Wetransfer Link okay for you?
https://we.tl/t-aOLvfEIbTm
I provided the Spine files of both skeletons and a third Spine file where I imported the weighted mesh.
I did the following when I encountered the issue:
I made a skeleton consisting of 3 joints and two image slots, one slot for the face and one for the hair. I turned the hair slot into a skin placeholder. The Hair was turned into a mesh and I added skin weights.
Then I repeated the process and made an identical skeleton in a separate Spine file. All the joints and image slots have the exact same naming convention with exception of the skin name, which would be "Hair2" instead of "Hair1"
Then I made an export file of The hair2 skeleton and imported it into the Hair1 Skeleton. The Hair2 skin showed up but the mesh had subsequently collapsed.
The goal was to test if the skins of one rig can be copied to another like we can do with animations. I managed to import meshes from one skeleton to another but not when the mesh has weights.
I hope that clarifies the issue. Let me know if there is still something you don't understand and thanks already for the time!