OK, I read the OP and skipped most everything else as I'm not that interested in the theological debate, but the OP got me to thinking somewhat and here's what came out:
(This is all from the JW-type view of things, BTW--I know most non-JW Christians on here don't agree with the WTS interpretation of, well, most anything.)
So, Adam and Steve (Eve is a mistranslation, yes, it IS Adam and Steve!) were in the garden for like, what, a full week before they F'ed it up for the entire human race? They were perfect, and yet made a horrible mistake like right off the bat.
Given the above, and the fact that there will be millions (?) of people around the instant paradise-earth is reestablished, what's to make one believe that some other "perfect" human wouldn't F it up big-time, yet again, within say--five minutes?
If your answer is "Well, Satan won't be there, so it'll be all good," then you're admitting that it wasn't really Adam or Steve's fault in the first place, it was Satan's--I mean, they didn't know God from Adam (well, you know what I mean), they never saw God, but here's this talking snake they can see telling them the fruit's all good--if this was the first lie ever, and they didn't have the knowledge of good and bad, they didn't know what a lie was, and free will is a cop-out.
It'd be like taking a 5-year old, having their mom tell them not to each the chocolate ice cream that is sitting in a bowl in front of them because it's poison, then having their father come in and tell them to go ahead and eat it because it tastes good and it won't hurt them--and then condemning all of mankind from that point forward when the kid goes for the chocolate.