Great find Cody, thanks for sharing it.

The banjo player is probably Terry Bertrand, he played with the Balfa's some. I think dad played with him some also, maybe he'll chime in here.

I would never have thought I would have liked the banjo in Cajun music, but the first time I heard it I really liked it.

I think you are right because it doesn't sound like Bill Keith. I don't hear any melodic licks in that recording and that is Bill's style. He would have worked up a great melodic break if he was playing with the Balfa's. Instead I hear Scruggs back-up licks. But I agree that the bluegrass banjo worked very nicely in that song.

I once bought a cd in France.
Legendary Masters of Cajun and Creole Music.
Les Haricots sont pas sales.
On the Cd there's a version of J'ai été au bal,
with Terry Bertrand on banjo.
In the booklet there's a photo with
Rodney, Will and Dewey Balfa, Bois Sec Ardoin,
Canray Fontenot and a banjo-player.
On the second link you will find the CD.
It's also possible to hear the song with
Dewey Balfa calling , banjo.
All the recording on the CD are done at home
off all the great artists on the CD.