I don't think those people will be disappointed if it's something else. They are just used to it being Ancients, the text being used is Ancients, so they assume it's Ancients. I don't think managing to surprise people with something beside the default answer for every mystery in the game will upset them. I may end up eating my words and people rage over whatever Solution 9 is, myself included, but that'll be six months from now and I'm banking on no one remembering this conversation by then.