The group is free to join! Just click on the "Join Group" button on the top bar.
Unfortunately, there is an issue with submitting deviations at this time. The Founder tried transferring that responsibility to the contributors, but something went wrong and we are locked out of checking member submissions. The Founder has stopped answering my DMs about two years ago. When you become a member, you can try adding it into the group. I'll see if the error has been fixed or not.