It is complicated. The original game and the ETO mod where originally developed by Russians. Girl Life was originally just a English translation of the original game plus the ETO mod. But after the original game stopped we that worked on Girl Life started to develop the game on our own while a group of Russian devs developed the game as well. We had some talks and we shared some stuff, but in the end we both went in different directions with major code improvements and it became to much work to share assets anymore so we stopped. I heard but I don't know if it is true but that game eventually ceased being made as well, leaving only Girl Life. Then a few years ago again not sure exactly when, some Russians started translating Girl Life back into Russian and there version became a Russian translation project of Girl Life, which was originally a English Translation of the main Russian game plus the ETO mod.
Since you mention Niko, he is from Girl Life someone one of the devs from Germany created, so you are indeed playing the translation version of the game.
The only reason why it came up that you was playing the Russian translation is we have heard from others sometimes when they translate it, that it occasionally causes code issues. We don't know why, as we have nothing to do with the translation project and the people doing the translation work have never asked for our help, we know little about it. Other than occasionally hearing from players like you that is playing that version of the game, which is why we know some odd bugs show up during translation.
Anyways this is kinda a history lesson about the game and to explain why the coder mentioned they could not replicate the error with our English version of it, which makes them think it was a bug caused by the Russian translation, causing a problem with the code.
But since you got it working that is all that matters, hopefully you enjoy it. I would be curious to know what you and other Russian players think of the stuff we from other countries have added to the game. We know it has lost some of it's Russian feel, since none of us that work on Girl Life is from there.