Basically, it is an M code (1990) and says, in French, something like "Manufactured in the United States" according to Google translate.
My GUESS is:
The EU started in 1993, 3 years after this grill. Although, there were pre-cursors like the EEC. If memory serves, the it was the EU that really created a true common market.
So, I suspect in 1993, France had laws (similar to US laws) that require the country of origin be placed on items sold within France that are manufactured outside France. Although "Made in USA" appears on the vent is in English, the greater glory of France required it to be in English.
After the EU was enacted, I believe they would have to put up with the three "main" languages under the EU, English, German or French (my understanding is that France insisted on the French, for the greater glory of France), so you will probably not see this on grills sold in France from around 1993 onward.
I would happily trade you for a very nice Lobster Thermidor & a dozen fresh croissants.