runHuntingQuery API and 'evaluate pivot'

Seem to have a problem where any request to the  runHuntingQuery API with 'evaluate pivot' fails with 

error": {

        "code": "UnknownError",

        "message": "",

Is this just a 'feature' ?  The query happily runs trough the website/XDR portal. :-(

Is there a way to simulate a pivot (easily) in powerapps ?