These men will be highly experienced in 'dealing' with questions.
Unless you too are experienced in debates of this kind then you won't get anywhere; not because you are wrong but because you are unfamilier with the techniques that cult trained minds use to twist things.
I suggest you keep a low profile until you are more sure of yourself, it does nobody any good to fall into a shouting match. Besides, they may be looking for an excuse to DA or DF you, in my experience that's what sheperding calls out of the blue tend to be.
If you WANT to go for it then I suggest these for a start:
Do you believe a loving God would kill over 6,000,000,000 people? Why has the Society said the end is “soon”, every day since 1884? Who besides the Society says the temple was destroyed in 607 BCE? Why is protecting that date so important to them? Would a “just” God give all women extra punishment (birth pain)? If Adam and Eve didn’t know evil, why blame them for being fooled? Do you really believe lions were originally designed to eat grass? (see the thread 'God made cats' for more info on this)