My reading of Kortzfleisch is that there was only one Sharpshooter company, the 3rd, (see p158) who were dressed in green and were assigned to the 4th Division. As far as I can see jager describes all the individual soldiers in all companies and not the individual companies or the regiment. In Wellington's dispatches they are not referred to as jagers but as the Duke of Brunswick's Light Infantry. Also the Paylists for the regiment, in the National Archives at Kew, refer to them as the Duke of Brunswick's Light Infantry.

My forthcoming book on the 5th Division at Villamuriel is partly based on this understanding so I hope I have read him correctly. (Please excuse author's OCD)

All the best

Garry