It is Broken!!
I have studied the source code on BitBucket and tried to test an undocumented demo/test (Bitbucket) for meshview in 3D myself with the latest version of dolfin built from source (Bitbucket).
Serial solution: python3 demo.py
Parallel solution: mpirun -n 35 python3 demo.py
So basically MeshView is not working in parallel!
If you have similar problems then do not use MeshView.