Modding Gossip Reports Text

[Ymir9]

I've been trying to shorten the gossip report strings to make them more legible (the strings that read "Your Delegate {name} has discovered that...")
Although Gossip_Text.xml seems to contain all the strings for gossip sources, I haven't had any luck modifying those strings through XML. Even editing the original files in the Assets folder doesn't seem to have any effect in game. Does anyone know how to edit BaseGameText strings?

Much appreciated!