Hi,
Right now, it's unknown how these achievements work (or don't work). Some uncharted missions did actually grant the achievement (i.e. reporting to Helena Blake), some had no effect, even when the mission transferred into completed state while still being offshore.
What I can advise in the meantime is doing Citadel assignments with the remaining members. Those always worked for me. There is quite a lot of those if you haven't done them, so if you keep count, you can probably grind out all your remaining achievements. Check Citadel assignments on the Wiki Page if you're unsure.
Reporting to Garoth and Adm. Kahoku after his first quest at the Citadel Tower also count, and there's also Nassana's mission that goes into completed state when you go back to her at the Embassies. Just make sure to switch around your crew at the Normandy before turning the quests in.
Main missions should also count.
