I'm sceptical about this. I did some research research into it years ago when somebody contacted me from France, when I was working on
Operation Dragoon, but I couldn't come up with any evidence that
Jagdgruppe 200 was involved in St. Exupéry's disappearance.
Rippert's claim is not in the surviving lists, although one of his from a week before 31 July is and another JG 200 pilot's claim is recorded for 30 July. Claims by the
Gruppe from August 1944 were recorded however.
The relevant ULTRA decrypt is XL 4317 on file DEFE3/65 (
Fliegerdivision 2 operations for 31 July 1944. I would need to search for my copy of it but from memory there was no indication of any success by JG 200 that day.
Nor did I find anything in No. 276 Wing's Signals Intelligence logs (intercepted W/T traffic) although other JG 200 combats do feature there.
There are further research possibilities in files released more recently but I have not had a chance to check these out yet.
Of course because there is nothing in the records, that does not make it impossible but deciphered daily operations reports from Fl.Div. 2 seem to be present throughout the Summer of 1944.