Like i said, delete all his data from the dabase (phpMyAdmin) and import his data back in from your backup file.
Simple process, wouldnt take more than 20 minutes max.
just search your phpMyAdmin database to match the account ID and change the values withing the feilds, its a longer process for just one account but it wouldnt take long.
Or simply do a search for the account ID and delete it all then import your backup with the only one account.
download the latest kRO and fully update it, then use a GRF tool to extract the map files from either data.grf or rdata.grf. Id do it my self for you but im in work