Gwydions it hints were the ones most likely to obey the call and go. Possibly oath bound to do so. Hard to 'stay and fight' if you're going to be hit by Banality AND an Oath if you stick around but they do have some that claim the stuck it out. Varich have always had their section of the House that disagreed with the majority and some stuck around. Daireann's son, Conchobar held the gates..perhaps some of his personal guard got on the other side. Dougal tried a peaceful transition, but many of their sidhe that did remain were hunted down..whether they got the changeling way first or not I'm not sure.