Of course with applications for the medal only being invited in 1847, with the first medals issued in 1848, the medal was “survivors medal”, and NoK were not eligible, so if your man died in 1845 he couldn’t appear on the Roll.
As well as muster books, the regiment’s Description Books are at Kew.
I too live too far away from Kew to make it cost effective to attend in person, but I found I could employ a researcher for several hours for half the price of getting to Kew. I have no connection to any but you could consider that option.
For a the name of a researcher that offers that fixed price package use your web browser to search for “military research on line” or go to the NA’s web site at http://www.nationalarchives.gov.uk/
> Records > scroll down to Paying for research