I had a similar situation some years ago (in the good old Flying Dutchman days, just before the Flying Blue enhancements were made). I called FD helpdesk and they changed the "taxes" on the award flight to the level of the revenue flight. (I was Platinum Elite at the time). A friend who was only a lowely Silver Elite also called and was told to get lost. Only after he referred to my case they were willing to adjust the "taxes".