Simply ask them to explain how they plan to BE resurrected and/or live forever, dear Rox (peace to you)... without having to personally heed Christ's words recorded at John 6:48-58. When they respond that they can/will live forever because they "have life within themselves," ask them how that could BE... in light of his words at John 6:51-53...
"UNLESS you eat the flesh of the Son of Man... and drink his blood... you have NO life... within yourselves."
... which you most likely will have to return their attention to because they most probably didn't REALLY see/read... and COMPREHEND... those words the first run through (JWs are programmed as to what certain verses state... or mean... and so their brains automatically go to those programs when they read the Bible. Well, when they read virtually anything - they always see things with a WTBTS "slant", so you may have to redirect them back and have them read it again).
Ask them WHY, if CHRIST said what HE did... they and the WTBTS teach something different. Then watch the wheels begin to turn in their heads. Seriously, you can virtually see it. They go through their mental "files" TRYING to find/recall some WTBTS explanation. They get to the one where the WTBTS says such verses "don't apply to everyone, but only the 'anointed/little flock/144,000". But the words "anyone" (in verses 50 and 51)... "in behalf of the WORLD" and "will live forever" (verse 51)... "Unless" and "no life in yourselves" (verse 53)... "everlasting life" and "resurrect... at the last day" (verse 54)... and "live forever" (verse 58)... won't let the WTBTS teachings process. Rather, a very SERIOUS event of cognitive dissonance occurs... one they simply CANNOT deny.
Note, you may not get them to walk away from the WTBTS right then and there (then, again, it depends on the person and where they're actually "at" in their thinking as to the teachings of the WTBTS... as well as whether they've heard the "call" personally but have hesitated in responding up to that point...), but you will have DEFINITELY planted a seed (of doubt about the WTBTS and its teachings which, if further "watered"... will "grow". Perhaps to the snatching of such a branch "out of the fire")... because this issue... who should partake/who should not... is THE major issue that separates the "haves" from the "have nots" in the WTBTS.
Sure, the thought/fear of "Armageddon" keeps 'em scared... but the bottom line is that they want to live... FOREVER. When they see, with their own eyes, however, that how they've been told they're gonna DO that is NOT "what the Bible says"... a HUGE "glitch" occurs in their processing. It cannot be helped. First they go, "Huh? Wait... HUH??"... then, the cognitive dissonance... and then "other" questions start bubbling up in them, as well. Because if the WTBTS has THAT wrong (and most already "feel" as if they do, but don't have the heart to go against the "FDS")... what ELSE do they have wrong?
Has worked for me more times than I can count. Many. Numerous. Indeed, it's the only thing that has caught the attention of those I've brought it up to... and helped out. Of every age. Everything else they try to explain, justify, dismiss, etc. This one... they can't. Says it right there in black and white: ANYONE can... ANYONE who does will live forever/be resurrected... and UNLESS one does, no life in themselves.
Oh, and it really only takes about 2 minutes, so you're well under your 5-minute limit, dear one.
Trying to TELL them the truth... about the "truth"? Won't work. They've been conditioned to expect, defend, and repel that tack. You've got to show them... FROM THE BIBLE... where the WTBTS says one thing... and Christ says entirely another. There are other subjects, yes... but they will look to Paul (who often wrote things different from what Christ said/taught)... so that won't work. You have to use something that Christ... and PAUL... agreed on. This is that thing.
I hope this helps and, again, peace to you!
A slave of Christ,
P.S., If they bring up Paul's words at to "eating and drinking unworthily"... which they will, because that is the OTHER great "fear" instilled in them by the WTBTS... simply ask them who, at that time, would NOT have eaten and drank, given that the way was open, by their account, until 1935 or so? Then tell them, "Surely, Paul was referring to something ELSE when he penned those words"... and then read THAT account. Once they even think the WTBTS might be wrong in their teaching as to the first (eating and drinking), they will be able to consider that it might ALSO be wrong in their teaching as to the second (what it means to eat and drink "unworthily"). The account itself will clarify what Paul was referring to... and without the WTBTS "blinders"... they will see that, as well. Another 2 minutes to spend, perhaps, but still under your five. I doubt, however, that THEY will want to end the discussion that quickly, so be prepared to go beyond the 5 minutes... but by this time, at THEIR request. Again, peace to you!
P.S.S., Of course, if you don't believe in God and Christ... and simply want to get them out of the WTBTS... without maintaining any shred of faith in God and Christ... then forget everything I posted above. No point, really... because if you want them to believe there IS no God... you're gonna have your work cut out for you. Besides, if YOU don't believe it, the likelihood of helping another believe it is slim... to none. Again, peace to you!