Great job finding this link. Only a few more steps before you can meet the community. Once your application goes through, you'll receive an invitation via Discord's direct message (DM).
Due to how Discord works, please know that if you're new to Discord and not in the BSMG server, someone will send you a friend request to enable the DM-ing function (after a while). It is recommended that you join the Beat Saber Modding Group's Discord server first and familiarize with the big community to get a faster response.
https://discord.gg/beatsabermodsWhen we are already in a mutual server, all that's left is for you to enable "Allow direct messages from server members." in the Privacy & Safety settings.