So, MJSU fixed Discord Auth and released the update here on umod. Now there's an error that pops up when a player is removed from the authenticated Oxide group from Discord Auth:

[Discord Extension] [Error]: Discord API has returned error Discord Code: 10007 Discord Error: Unknown Member Request: [GET] https://discord.com/api/v9/guilds/831601204677050420/members/1002347368919871568 (Response Code: NotFound) Content-Type: application/json
Discord Errors:
Request Body:
Contents is null​

MJSU says that this is an issue with Discord Nitro Boosts that is popping up since Discord Auth is now fixed. I can say that Discord Nitro Boosts does seem to be working, as players that have boosted and then stopped boosting have had their Oxide role removed. I don't know if this error is causing any actual issues.