Ok, strange. I couldn't replicate the CTD. When I originally got the crash, I loaded the save, tried healing Emma again, killed the aliens, then CTD on mission complete. After that, I reloaded the save again, DIDN'T heal Emma, killed the aliens, and no CTD on mission complete.
But now, after inserting the save file back in, then reloading, and trying to replicate the original CTD, it doesn't work! I am a bit confused, as loading the save earlier still resulted in CTD, but now I can reload the save and it's fine? Very strange. I have still had trouble with crashes since my first report here. All to do with the medkits. Either CTD on heal, or CTD on mission complete, after heal.