I don't know if he really knows who he is, but he is probably the most credible person to come forwards claiming to know or be him. That itself is not really difficult with the string of charlatans who have pretended in the past, but it is entirely possible given his past that he does know and again entirely possible this is just another John McAfee PR stunt.
John McAfee credible?
Does not compute. McAfee would say anything as long as you paid him to do so. He's either trolling or is on under the influence of drugs, but either way he only has his own interests heart so he's only saying this for his own agenda whatever that may be. I would say with a strong degree of certainty that he doesn't know who satoshi is. He's probably just doing this for the attention to be honest. He's built his brand these last ten years or so by courting controversy and getting his name in the media and this is along the lines of the same sort of shtick he's always done.