Cumqueror

My goal is to create a warhammer 40k themed mod that will have different custom commander voices for each nation. Replace german voice with necron, france with ork and so on. Only way i see this happening is to unpack all naton voicing to "res_mods/banks/Languages" and edit them. And thats working except one major problem - after one single file is placed there, any voiceover mod disappeared from game settings. Only standart one left(screen attached). When files removed all is back. I spend few days trying to fix this, but nothing worked so far. Can anyone help?