I don't believe that just because someone else is a Jehovah's Witness, that they will be damned to hell. Neither do I believe they are deluded in believing in any sort of paradise. It may not be the one they expected, but I believe there is one. I also don't believe that there is "no Paradise or anything else." How could anyone know that for sure? Atheists sometimes have just as much of an arrogant way of looking at things as a Witness.
Since we're all dealing in theological predilections and personal beliefs, my own view is that, upon death, Witnesses will immediately become aware that they are mistaken because they will be aware that there is no continuity interruption. They will still be alive.
I don't base my personal beliefs on the Bio Channel, but I do believe there are too many unexplained phenomena to just sweep it all under the carpet. There are enough experiences related there that it makes me believe there are probably those on this forum who have had experiences with the supernatural. To say there is no "anything else" is very narrow minded in my view.