I could be wrong, but wern't the Aliens in AE just plastic and not animatronics? I don't know why they would want to keep those. After that many years of all the steem and such in that ride I would guess that they're probably not in the best condition and not worth saving unless you're a big fan of the attraction. As for animatronics, I know Disney usually doesn't throw those away. They're too expensive to just do that. I know that a lot of them are recycled in the parks. Some of the animals on Jungle Cruise, for example, were originally from WOM and I believe that the Native American villiage on the WDW Railroad was expanded a few years back with either animatronics from Horizons or WOM (not exactly sure about that though, so don't quote me on it).