Did you get the acheivement post 2.1.1? I've done Foundry 4 times (pre 2.1.1) & have yet to get the acheivement on Normal Mode. I did finally find a known issue on it (wish i had found it before I spend 4 hours on the mission
) but havn't seen that it has been fixed.
I had the Foundry sm achievement before 2.1.1., did esseles, Taral V, Kaon & Lost Island after that and now have the "complete all sm fps" achievement done. So at least that one doesn't affect all players.