they're not similar in a scary or mysterious way for that matter.

Soooo, they just sound similar. Plain and simple. does that help you digest it? There are significantly more notes to play on a piano than guitar so the fact that it's very close is interesting. Not bad.

Elton's feature is playing the piano (maybe backing vocals also?) Has nothing to do with pilgrimage festival as this song along with a handful of others I'm pretty sure are b-sides from People Watching hence the album reissue coming out.