Since the SL uplift to amazon servers, offline group invites are nonfunctional.
The reinvite boards at the arrival point (both main sim and seaside are either failing to detect group approvals or silently failing to do anything.
As noted before the registration boards both for the observer and the forum are failing to contact the servers.
I know some of these things may be technically challenging to fix, but I don't think a single person who can only handle invites if both themselves and the recipient are online is going to be sufficient. LL are not likely to get the issue fixed in the near future, as the issue has been triaged, but has not been assigned to a dev (meaning they won't even really look at until Q3).
I know this really doesn't affect me or current players much at all, but it's an unhealthy state of affairs for the sim in general and I'd really like to see this place grow and get stronger. We have a lot to offer new folks, lets not run them off before they can even get in the door.