Peter R. Arnott (born 1932) is an American composer, theatre director and banjo player. Arnott is a member of the Bohemian Club and has been closely involved with a number of Grove Plays. Arnott is a founding member and banjo player for the Goodtime Washboard Three.
Peter R. Arnott plays many instruments.
The article doesn't state he only plays banjo, and it also doesn't say he plays other instruments. It might have tricked the model because of the wording of "instruments"