Just a few points of view from me on this. I haven't watches the video, I doubt it would convince me one way or the other if it was genuine or not. But on this topic...
I'm a christian and I believe God does heal. Some others are christians but don't believe that God heals. In the same way, some non christians may have views either one or the other, and that's fine too.
My mum was dying of Crohns when she was a child, and she was expected to die, but she was healed, so without that having happened I wouldn't be here. Unfortunatley for me, God hasn't healed me as of right now. I don't know why, but I don't believe he heals everyone, and I don't think it is because of a lack of faith on my part. Maybe one day he will heal me. I hope so. But maybe he won't. I would be lying if I said it didn't challenge my faith being in this situation, but at the same time, my belief in God is not conditional of God guarenteeing me health.
Regarding addictions, many require much more than mind over matter, or change of belief. Heroin for instance is usually a serious addiction and even if you want to, you can't just go cold turkey, no matter what support or beliefs you have. You need to come off gradually, or have replacement because your body is addicted. So such instances where true drug addicts are healed of their drug addiction often can't just be ruled out on the basis of substituting one belief for another. In my opinion some people are spiritually healed of their addiction, same as other illnesses, though that doesn't mean that everyone who claims to have been healed has been.