Without seeing your data setup it's difficult to tell what is wrong. How is the UK nation defined? Can you post the nations.txt file?
The string Text files are loaded in numerical order and the contents of the higher numbered files will replace the contents of lower numbered files IF there are identical string IDs. So if you put your soldier names in Text1.txt they will override Text32.txt if the string IDs are identical.
If there are more string IDs for a nation's soldier names in Text32.txt than in Text1.txt you'll get all of the names in Text1.txt PLUS all the names in Text32.txt that are not matched by an identical string ID in Text1.txt
If you have the setup defined above, you'll see the names "Name0", "Name1", "Name2", and "Name03" in game.
If you do not want to see "Name03" in game you either need to delete it from Name32.txt or add an overriding IDS_SOLDIERNAME03 in Text1.txt.