You copied your event and noticed that a lot of players on the scorekeepers list shouldn't be there. 

In that case, before making your event, division  and round-robin public, you want to clean up your rosters and/or players' list.

Even though you see them on the list, if it's not public yet, they don't have access. Once you clean up your rosters, you will start to see that the scorekeeping list cleans itself up automatically.

Once you make the Event and Division public, players get notifications saying: Hey we noticed you are playing in this league, is that you? (in other words?)