You're right about the villages all being south of Sedan, but it's not about the German invasion of France in 1940. This (Manhunter) chapter certainly has the US army placed in a 1944 context.

I tried some internet research, but nothing really valuable turned up, except one article speaks of German 'Lagers' in that area. However, Paris was liberated by the end of August '44, Brussels and Antwerp one and a halve week later, by mostly British and Canadian troops under Montgomery. Patton's troops were heading towards Metz and Saarland, therefor it must have been the US troops under Bradley heading for the Ardennes, somewhere in September or October '44.

Also, the chapter map shows what seems to be a military plan with some pretty detailed troop information. 71st Infantry Regiment is mentioned, next to some Free French troops... Searching on internet about the 71st Infantry Regiment results in an article that states:

The regiment departed from Boston on 5 September 1944 and landed in Cherbourg, France on the 15 of the same month. The first companies of the regiment entered action on 23 October 1944, when they relieved elements of the 70th Division in the vicinity of Embermenil, France. In the last weeks of October and the first weeks of November they drove the Germans from their strongholds in the Foret De Parroy, France.

Embermenil and Foret De Parroy are on the right of Metz and Nancy and 71st was heading for Saarland, so that would make them part of Patton's troops, i guess. Strange story indeed, because Chéhéry, Bulson, Villert, Chémery and all villages mentioned are far on the left and north of Metz, close to the Belgian Ardennes. Maybe they passed Sedan on their way to Metz and Nancy... i'm not sure.