My music library includes files with Funky Unicode Names and I have no idea if it's Android, KDE/Dolphin, or the SD card but it regularly eats entire albums and doesn't show them in the media library nor file browsers even though the files exist.
I mention KDE because as far as I remember this didn't happen on Windows. I'll have to try and copy them via MTP on it. MTP transfers of these cursed files always fail on Dolphin.
Definitely some filename fuckery going on. Taking a file from the folder and removing its funky naming totally lets me chuck it at the phone, no questions asked.