I don't know if the umap files contain all the texts but I know there are texts (there is not much text in this game) in other files umap. If you search for the word "the" in the text extractions of umap files, you find this word in at least ten files. In the attached file, all the texts extracted from the files umap + the result for the search "The".
This is the Zeneth_Central.umap file which is also linked in my first post. File: Zeneth_Central.umap Apparently, the game.locres file currently contains only part of the text of this umap file. I think there are also other missing texts but I have not detected them yet except some text of the settings.
I confirm that these texts belong to Zeneth_Central. Umap
But I found that this text had no key like the rest of the text of this file. Maybe that's what's causing problems for the extraction. How do you get and / or modify this Game.locres file? Are you using the Localization Dashboard of Unreal Editor?