This gizmodo article reeks of sensationalism. They go so far as to say half of his face got "older and wrinkly," while the other half stayed "exactly the same," even though it's plainly obvious that all of his face has aged, both sides have wrinkles, and the half that was struck by the beam isn't the same as it was since the accident. At the very least I'd love to see more information substantiating the claim.
This doesn't seem all that crazy to me. The Wikipedia article says that the left side of his face is paralyzed because the corresponding nerves are destroyed. The left side of his face may not wrinkle because the muscles do not contract. This is similar to the mechanism of Botox, which interferes with nerve terminals at the injection site.
EDIT: Also, one of the symptoms of Bell's palsy, which is a form of paralysis of the cranial nerves, is fewer wrinkles on the affected side of the face.
An article explaining part of the reason why I'm suspicious: http://www.washingtonpost.com/posteverything/wp/2014/07/24/i...