[Closed] Barn2 Product Option plugin translation issue (Visual Editor)

Background of the issue:
I am trying to get the translations to work in general, but not for the Visual Editor of Barn2 Product Option. I made a support ticket to Barn2, but they said WPML promised translation works 100%, and since it apparently does not, they asked us to get in contact directly with WPML support team. Link to a page where the issue can be seen: hidden link

Symptoms:
I see most of the translations are visible, for example, 'Étape #3' and 'Option'. All translations are there but not from the Visual Editor fields in the Barn2 Product Option plugin. The text on the French page (and Danish and German) is still in ENGLISH (the original language).

Questions:
Why are the Visual Editor fields in the Barn2 Product Option plugin not translating?
How can I ensure that all fields, including those from the Visual Editor, are translated correctly?