Gents,
Fabry (Campagne de Russie) vol 5 has a "Situation" dated 30 June showing "7e Regiment de lanciers" under Zawadzki in IVe corps de cavalerie. Here is the cite:
http://gallica.bnf.fr/ark:/12148/bpt6k5768412d/f1219.image.r=Fabry.langEN
johnwladis