Fallout 3's Nuka Cola Challenge quest rewarded you a low ranking bronze trophy even after you spend 5-10 hours doing the quest. However, almost all of Sly 2's trophies were unmissable and story related, and took me only hours to platinum.
Yes, i think. in the combineover wiki (The half life wiki) it says that she survived the explosion. in my opinion though, shes probably a gonner. I f she survived that blast, she would have BARELY survived.