Well after playing the Co-op Split screen Terrorist Hunt in Rainbow Six Vegas twice! I knew there was something wrong when I didn’t get the achievement the second time around. I figured… ehhh I must have forgotten a few stages or something but nope… I played all them through and no achievement… I was a little ticked off! So I asked around and I was told that there is some sort of error or glitch to where you can play the Single Player Terrorist Hunt and get the Achievement for the Co-op Split screen Terrorist Hunt. So I played the Single Player Terrorist Hunt and sure enough I got the Achievement. So if you plan on getting the “Co-op Split screen Terrorist Hunt” Achievement take my advice and just play the Single Player version first and save yourself some time and headache.