My father was with the 11th R, 5th Div., Co.I and took part in that same campaign but just a bit down river at Dornot. M.Yves Bellanger has a site w/ pictures and info regarding the movemnet to take Metz. My family and I visited France this summer and met a wonderful couple, the Gozzos, who have formed an association "thanksgis" and have a museum and a website dedicated to the 5th Div. All the small villages in the area have plaques honoring the Americans. They should also have info about Ft. Driant...we were taken to the area, but did not talk about prisoners. My Dad came home, and as you mentioned, never talked about the war, although he did remain in the military for his career. he has also passed away and we have found in the "family archives" alot we never knew.
Elizabeth and Alain Gozzo site:http://www.multimania.com/thanksgis
Both of these have specific info, maps, and if you write Alain or Elizabeth, they can write you back in English if need be. They do extensive research in the US Archives and are still finding lost soldiers and sending their remains home. Special people! Hope you find this of interest. Linda Dobbs