Fugue has a definition, one is for music, listen to it to see if it fits the definition. The other definition is for medical psychiatry dealing with amnesia.
The psychiatric definition is that overwhelming Force power that overwhelms the user and causes amnesia.
In the Fanfic, Thrawn may have had the Force, but grew out of it. It appears like “Ender’s Game”
The question then becomes who is the ROOK in this Chess game. Sure, Thrawn can swindle people, but his life would be short-lived if he did.
From understanding the art, the better access to the art.