Wow, nice thing to read about, it can make you think indeed. I won't say that this is true or false, I have no idea what the reality is, but as a fact, indeed Reiki is a real business lately for some people. And yes, it can be dangerous for some without proper guidance. More, this energy can do harm, not only good, depends how some people want to use it.
I think this is a good thing to read and then find out more about this subject if we are interested, at least we can take a decision after knowing more, not just seeing a good or a bad part of Reiki

You will never know that fire burns until you touch it.