Where do I find subtitles for foreign film that were only use for cinema and not for home release

I’m currently looking for the English subtitles for muroi shinji not defeated https://jfdb.jp/en/title/10263, I seen that it had a English translation but it’s not been found and is hard to find, it seems it was only use for cinema, maybe even a film festival, it seems to also be available for airplane films, I was wondering how I would be available to get a hold of it.