That's not how things work around here (or any Disney fan forum for that matter).
I'm a little nervous about this too, to be honest. I think the intent behind it is sweet, but I will be wondering about the execution until we have more information about how it will all be handled and how it will fit together within the existing attraction. The most logical possibility is either an entire rescore (probably not happening due to logistics required and Disney's, well, cheapness) or replacing the finale room audio, which I understand and think makes a degree of sense. However, I really appreciate the finale audio as currently scored, with the adult audio added in to really sell the idea of a culmination and an appropriate ending, that perhaps we could reach the point where the idea of world peace is something beyond just wishful thinking of children and something embraced by all. So, understandably I hope, I'm nervous that something that to me feels so perfect about the original show is at risk of being tampered with for the worse.
My preferred solution would be that some of the MANY English reprises of the song used throughout the attraction (notably more than any other version out there, including the WDW version) are swapped out with new recordings featuring the third verse, but I doubt that's what we'll end up with. I imagine anything less than a complete refresh of a given area's audio will sound jarring given the gap that will exist between the 60s recordings and those made today.