Your model looks perfectly Symmetrical to me!
Also when i was experimenting, i found that bets results are achieved when you turn off Vertex normals. Sometimes this can create black areas on your mesh, where the normals are messed up!
So, like i said i don't see a difference in your mesh, So maybe thats why can't see any results.
Other than that i guess you could make sure your transferring over the right axis. Maybe your model is mirrored over the z Axis??
I'll keep playing with setting to see what i get in Maya, but like i said it's working fine for me.
Try creating a Sphere and messing up one side, and try the Transfer Attributes on that. If it works then you know it's the model thats having the problem, and vis versa.
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