On https://fr.wikipedia.org/wiki/Kapla#Mesures_et_math%C3%A9matiques the 3D thumbnail is in a gallery, and is the only 3D file on the page. No 3D badge is shown when the page first loads:
After opening MMV and closing, the badge is now visible:
The badge is also visible if other 3D files are shown on the page as regular thumbnails (not in galleries).