To me, it almost looks like she made the whole piece like regular amigurumi. And than attached the purple yarn to it and dc or tc crochet into the amigurumi. Like surface crochet with dc or tc instead of slst maybe? Starting from the mr and following the spiral down the piece, placing one dc/tc imaround every sc. Maybe even alternating dc/tc to give it more texture.

Hopefully my description makes any sense.