Gunter, Geert & Mark,
I can confirm that Frederick von Wissell was present at The Battle of Waterloo commanding the 3rd Line Battalion KGL, for which he received the British Waterloo Medal.
He succeeded to the command of the 1st Brigade KGL and held it until 8 August, when he was replaced by a senior officer. He then reported to Lieutenant General Charles von Alten now commanding the Hanoverian Reserve Corps and it most likely then received command of the 4th Brigade Hanoverian Reserve Corps.
Major Frederick von Lutterman as senior Major of the battalion would have commanded it in the absence of von Wissell.
I have killed 18 June 1815:
Captain Frederick Diedel
Lieutenant Frederick de Jeinsen
Lieutenant Frederick Leschen
I do not have "[Friedrich von Jansen severely (killed) is not mentioned in my list]" and wonder if this is an error for Frederick de Jeinsen?
Hope this helps.