If you don't like the script, go to this folder: C:\Program Files (x86)\SEGA\Medieval II Total War\mods\Third_Age_3\data\world\maps\campaign\imperial_campaign
Open the campaign script file and delete everything between 'Baron Samedi/KK's One Ring script' and 'HELP WEAKENED FACTIONS' script.
It's quite some lines to delete, but if the script is a bother to you, it's not that much work.

Oh, I almost forgot: no resposibility is taken for the statement that the ring script ends just before 'HELP WEAKENED FACTIONS', as I have messed with the campaign script before

Your solution is definitely another possibility though
(For everyone else reading this and wanting to get rid of the script: make backups in case you mess up or want your script back, be very carefull and use Notepad++ to edit just in case).