Yes I put the json files in the acf-json folder in my theme folder and then choose to sync the field groups.
I then deleted the json files and tried to import them through ACF Tools / Import Field Groups. This time everything works as it´s supposed to. The field group is of type clone and the values are fetched the way they should.
I´ll test this a bit further tomorrow when I´m at work.
Thanks for your help so far.
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