I can see the issue, thanks for the reproduction steps… I think this should fix the issues for the linked topic too.
The problem was that we were missing the fact that all users are part of trust_level_0 and logged_in_users (and default_invitee_trust_level) after redeeming an invite… the invite was requiring the invitees to be added to those groups in the invite process, but it’s not possible because they’re automatic groups.