Plee answer guickly and seriously?

hey,plz answer seriously, in splinter cell double agent 4 xbox, there r bout 3 different endings and 2 get them u hav 2 spare ur objectives lives,(jamie,sykes,moss) now wen if i dont kill jamie and sykes that line 2 swing on doesn't appear and if i dont kill moss it wont let me blow up that room under him.