I have a feeling you're trolling right now, and I'm getting a strong sarcastic vibe from the post. However, I'll take the bait.
I have a genuine 50 in my pocket. I'm a counterfeiter who is making counterfeit 50's. Those counterfeits do not negate the legitimacy of the 50 dollar bill in my pocket. I can still spend that original 50 on a dinner and movie (or a tank of gas). It's still valuable. (this is all hypothetical. I am not a genuine counterfeiter and I do not have a 50 in my pocket.
So just because some dillusional individual says the end is going to happen, and it doesn't, doesn't mean that the true end won't happen. Jesus is still coming back, and we still have a responsibility to tell the world about it. Sure it'll be harder because of Campings rantings, but that doesn't negate our responsibility.