Patty:
Caudill's 13th Cavalry was at different times during its existence also known as the 11th Kentucky Mounted Rifles, the 10th Kentucky Mounted Rifles, and- surprise- the 10th Kentucky Infantry! So it's not at all inconsistent that he would have a 10th headstone- unusual, but not inconsistent. You should try contacting the Ben Caudill SVC camp at http://www.bencaudill.com/ and ask for their information regarding Jervis' service in that unit. They have much more info than you'll find in the Adj. General's Report.
Randall