Sounds like two issues here. First is the admin not seeing all the users. Have you used the filter box to search for a user you can’t see? I’ve had the entire box blank but searching pulls up the user I need. Next I’d check the ACLs and do some debugging.
the other part of the question is having the groups manager add users. For this you would need to give each manager a role that would allow it and then write script in your ACL so they can only add/remove from groups they manage..
if my response helped in anyway, please mark correct or helpful
