So a fellow I host a few servers for from my VPS has come to me to ask me about this lovely little issue where SourceBans does not seem to want to get along with sm_addban.
Normally, he uses SourceBans in combination with some form of a "Ban disconnected player" plugin to ban people who bet on things (such as tic-tac-toe) and run when they lose to prevent having to pay up, but if I remember correctly the Ban Disconnected Player plugin(s) he was using did not get along with SourceBans.
Has anyone else had the "failed to ban" issue before? And does anyone know of a way to make SourceBans and a "Ban Disconnected Player" plugin play nice?