This all sounds like a login problem. You did not need to re-create anything. If you have a backup, restore it, and log in. If the site is nor recognising the password, build a temporary page to execute a forced password reset. Then the link will re-appear.
As far as the YAF search, I think this is the FTS index. You need to re-run the SQL to create it, or, as the message states give the current user dbadmin rights to the database.
.....the man in black fled across the desert..........and the gunslinger followed.....