This piece is mentioned in the notes on my Piece d'Orgue upload of a few days ago.
See the notes on Piece d'Orgue for the full description.
A likely model for the dominant middle section has been found in the Grand Plein Jeu Continu that opens Boivin's Premier Livre d'Orgue. The affinity are the Alla Breve metre, white notation and 5 part texture. It is possible it was originally written for pedal clavichord, the study instrument of choice for organists in those days, which had an extended pedal.
Could be, could also not be.
As I mentioned before, Ton Koopman once stated: "From the sources you can prove anything!"
Make up your own mind!