I’d say experiment on your own and find out. Your friend might’ve printed it wet and TPU is by my experience the most hygroscopic of them all.
You need to dry the spool first and then keep drying it as you print. Seriously. I’ve printed two small bumpers out of tpu recently and after drying the filament one of them came out fine and the other had zits and blobs just 20 minutes later. Its insane how fast it absorbs moisture and how much it affects it.
Yeah. Those bags hardly do anything when the spool sits for months on a shelf.