The Crash Tester Skin was only available for those players who participated in the Devolver Beta Squadron Pre-Launch Tests and logged into the game during the first month after the launch of the game.
I participated in the Devolver Beta Squadron Tests and Just Logged In?
Thank you for beta testing. Unfortunately, you would have had to log in to the game during the first month of launch to receive the skin. These have all been distributed at this time.
I'm part of the BoBs Beta Tests, where's my Crash Tester Skin?
This skin was exclusive to the Beta Squadron Pre-Launch Tests.