One problem from a Polish source perspective is that they would have served in Polish units in French service. These units are often overlooked in Polish studies. Gembarszewski's history of the army of the Duchy of Warsaw does not list any of these officers, while a recent Polish history of the Lancers of the Guard does not have anything on them. Nothing in Martenien's book on killed and wounded officers either. There is a published history of the eclaireurs you may want to try and find: Jean and Raoul Brunon, "Les Eclaireurs de la Garde Imperial, 1813 - 1814," Marseilles, n.d.