What's actually in the artist tag if you look in the Tag Inspector?
Well in MusicBee there is "
Ark Patrol / XYLØ", but in dBpoweramp inspector window "
Ark Patrol; XYLØ" and in foobar2000 under artist name "
Ark Patrol; XYLØ".
See here the MusicBee Tag Inspector

"KÜNSTLER" is artist in german.
In foobar2000 it works by the way. I also used foobar to seperate all artist tags, which works for FLAC in MusicBee, but MusicBee has problems with MP3.
EDIT:Here's the file: https://drive.google.com/file/d/1TAhfbTzkadOOoVuE8cEVPkIxJX8xaqoz/view?usp=sharingSong is freely available