The explosion cut at the beginning is slightly longer in the chibi version so that's why the silhouettes change

The credits should be
0:00 - 0:12.6: Tatsuya Yoshihara
0:12.7 - 0:18: Takaya Sunagawa (all the chibi part of the ED except the explosion)
0:18.1 - END: Tatsuya Yoshihara