Hi,
I have a problem with my computer at the moment and cannot access my records, but the 3rd Battalion as a whole spent the Boer War guarding POWs on the island of St Helena.
However, if you have this man's medals and there are any clasps attached, then he would have served with the 2nd Battalion in South Africa, either as a volunteer or by order.
I'll let you know when I get my computer fixed.
If I can find him in a database I have I'll be able to tell you more.
Ian