I have never heard any warning about folding waders, neoprene or not, so long as they are completely dry. When you buy neoprene new, they come in a box, folded. I would wash them by hand with Ivory snow and then rinse them well. Dry them inside out as well as outside out thoroughly. Fold them loosely and keep them somewhere cool and dry and I'm pretty sure you won't have any problem.
Maybe there is something about folding neoprenes even when dry, but as I say this would be news to me, which of course means nothing since you must keep in mind that I have no idea what I am talking about.