So you're asking how to make a script that will fight for you in a ban-war against another mod? This will not end well. You're basically hoping that the other mod will get tired of unbanning the guest before your script gets tired of re-banning them. So the other mod makes a protection script to keep that user from remaining banned. To protect the channel from this flood, another mod will need to choose which one of the two battling mods needs to be banned, and might decide you both need to go.
Maybe try talking to the other mod, and if you can't settle it between you, someone might need to take the issue up with the channel owner.