credits for this absolutely brilliant part:

音楽シーン
絵コンテ・演出：室井ふみえ
作画監督：中島敦子

原画：小島正士　石川洋一　香月邦夫　斎藤哲人
　　　 岡竜人　室井ふみえ

there is some editing so I cannot tag everybody, nor is there a point in tagging everyone because some dont have booru profiles and Nakajima redrew them anyways.

Norio has a note on his wikipage regarding the first cut of this scene:

10：夢の中でスカーフを煙の様にたなびかせて歩いているレイカを俯瞰とアオリでとらえたカット（このミュージックシーンのみ中嶋敦子作監）。他にも有る様だが未確認。

Even though he's not credited, given his relationship with Nakajima, it wouldn't be surprising for him to be here

This is something else what the hell