Images for "Le Guide" group channels are not automatically updated if the picture URL doesn't change.
In order to force this update, and you cannot change your picture URL, you have to send a request to Leguide via the email : email@example.com
Object : [YOUR STORE] : Images Update
The displayed images are not the same as the one I'm sending through my feed : http://export.beezup.com/XXX/LeGuide/YYY
Here is an example of products where the image is not correct ( updated from my side but not yours ) : product ZZZ
Can you please update all images from my feed ?
You have to replace http://export.beezup.com/XXX/LeGuide/YYY by the URL you send to Leguide :