The information I have is that Capt Menzies commanded the Grenadier Company. I suspect he was out with the skirmishers when the French cavalry attacked the 42nd.
James Anton's "Retrospective of a Military Life", 1841 tells how the 42nd had 4 commanding officers in quick succession at Quatre Bras. He also say Campbell commanded at Waterloo.
Hope this helps.
Regards, Peter Thorn