If you really want to witness to them, don't do anything to frighten them off. They are not on your doorstep to listen to you, they are there to save your life by teaching you their religion and you need to let them think that they are doing that. You must be a prospective convert, not an opposer, a sheep, not a mythbuster.
You make too many statements for him to take issue with and some of those statements are just your subjective opinion and are debatable. e.g. "Oh! So you have been through this kind of upheaval before... I think this is going to be a historic time in your religion's history.". They don't see it that way at all. All through their history there have been changes, all high control groups do it. They are conditioned to it. If you are going to express an opinion, try to make it one that you already know they agree with.
Ask a question you know he will want to answer, then shut up and make him do the talking, the thinking, the research. If you have asked a good question he will use all manner of tactics to not answer it and you have to really be on the ball if you are not going to let him off the hook. You need him to want to give you a sensible answer to that question, to make impossible promises that he thinks he can keep, statements that he can't find literature he trusts that support them, etc..