Yes, works
Checked my Blender file and indeed, origin what set to 0 for all child meshes. So in conclusion:
if mesh.getAbsolutePosition() fails
- make sure the pivot is set to mesh center (or wherever), e.g. in Blender Object->Set origin
- depending on your use case, make sure you call mesh.computeWorldMatrix(true). In my case (not sure about the playground) this was necessary.