So I've just read the first two books back to back, to my husbands dismay. But anyways, I'm not sure the Parshmen need to be outside to be transformed by the Everstorm. For the original transformations in that Highstorm yes they needed to be exposed and have a Spren with them but this is the Everstorm! Those spren and red lighting are zipping around in it, it was brought on by that song. Maybe that song of transformation lives in the Ever storm not needing to be sung by the Parshmen.
Rlain didn't transform so that is something odd though. Maybe he was able to escape thru the oath gate before he was changed?
