Compatible Skeleton Animation does not retarget the same on duplicate skeleton

If a mesh is exported from the engine, reimported as a new skeleton and mesh, and then marked as a compatible skeleton. Animation will have slightly different rotations playing on the skeleton.

Steps to Reproduce

1: Download and open attached repro project. (5.7)

2: Preview in editor and look at attached cone in character's hands. Notice small offset in rotation.

3: Set translation retarget mode to skeleton (Previewing animation data from skeleton ref pose), you will see a starker difference in rotation data.

The dupe_2 mesh was exported from unreal and immediately imported with no ref pose changes.