It doesn’t say what Herve Groundel was doing there, that is why he had arrived there just a couple of days ago. Was he a reporter or an aid worker or an official of some sort?
As far as I can tell, he's some sort of mountain guide who is also an amateur photographer. Lots of nature photos - including some scantily-clad female nature. If his captors figure that out, he's toast regardless of what the French government does.
One day, some western nation will respond to this sort of threat with a counter-threat to destroy every mosque within its borders - and then actually do it. It won't be us, sadly.