There's nothing in the game that says Fratley ever killed anything on his travels other than the three mages we witness him kill. In fact, Freya says "I climbed the highest mountains only to hear rumours of your victories", suggesting no-one is quite sure of what he has done.

Also, there were never any rumours of Beatrix dying. There were such rumours of Fratley's death. He couldn't have been much of a warrior if people were saying he'd died.