Multi-language journal, form entry requirements

We’re using OJS 3.2.1.4 with a multi-language setup, as one of our main journals is linguistics-related. Sadly, we experience some problems with the backend forms, specifically required multi-language entries for user registration forms.

I tried adjusting the journal language settings in just about every configuration possible, changing the default locale for our installation in the administration settings, all to no avail. I’d appreciate assistance in the matter. I’ve currently restored our original settings and included screenshots.

Currently, all form languages are active since both form and submission languages seem to be linked and can’t be activated independently and the journal receives and publishes articles in multiple languages. Deactivating these for a test didn’t help with the problem though.
ojsjournalwebsitesettingslanguage
ojsadminlanguagepanel

Thank you for your assistance!