I would suspect that the three achievements for Skills, Strategy and Sportsmanship points are server dependent as well, as the stats are uploaded -- not sure that they are actually stored in your harddrive's profile. Had temporary server connection difficulties the other day, and received no points for a game played -- potentially why?
I would get these to be safe. Other than those five, I believe you should be good. Been worrying about this myself. Scrambling to finish.