Yellow and red invariably is a winning colour combo.
On the subject of regimental identification, there are plenty of units to choose from as yellow facings were common among French dragoons. Note that the Wartigny regiment (I suppose this is the one you referred to as Wentigny) was disbanded in 1698 and obviously did not serve in the WSS. Potential contenders include :
* Vérac (1710 Caylus) : served in Italy 1701-1706 and Flanders thereafter (facings either yellow or blue depending on which source you choose to believe).
* Lautrec : Italy 1701-1706, Germany and the Rhine 1707-1712.
* Fontbeausard (1704 Saint-Chamond) : Served almost exclusively in Flanders except for a couple of brief stints in Germany, including the Blenheim campaign.
* Rohan-Chabot : Flanders 1702, Germany 1703-1704 (regiment captured at Bleinheim), Flanders 1705-1710, Germany and the Rhine 1710-1713. Yellow facings unconfirmed but probable.
* Pézeux : Germany 1702-1703, Italy 1705-1706, Rhine 1707, Flanders 1708-1712
* Chastillon : Italy 1703-1706, Languedoc & Dauphiné 1707-1710, Flanders 17012, Germany 1703. Yellows facings hypothetical.
Hope this helps.