They are all in PAE_scenarios.xml (sometimes these texts can be harcoded in scenario file). But if you fix them, you'll need to start a new scenario. It's a vanilla bug. Leader name + civ desc/short desc/adjective are freezed if they are specified in a scenario (or worst, in foreign language multi-forms adjectives are lost).
I changed the names and started a new game, but no effect. I guess the wrong names were saved into this scenario upon its creation...
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