It might be because of internet trouble... players dropping at the end af a battle.... then u wont get the achievements...... it kinda sucks sometimes. But yearh.... the achievements are aometimes delayed in my experience.... i got the "stranglehold" achievment 2 months after i completed it :)

And what goes for the "man the defences".... same thing i think...... All in all.... i get achievements a bit delayed sometimes..... wierd but ok with me..... at least i get them^^

And yes....... a lot of those achievments is only from MP..... otherwise it would be kinda unfair