Donna still hasn't given up.  She's talking about going to find jobs and the Emergency Government making things better. Sylvia, however, has almost broken.  She points out that the refugees have been stripped of their votes.  "We're nobody," she says in a dead voice.  (Strike Two, logic.  Why would being an in-country refugee make someone lose their vote?  They're still citizens.)

Singing comes from the next room and Donna storms out, calling Zorba "Mussolini" and threatening him if she hears one more sea chantey.  But her temper tantrum cuts off when she finds Wilf in the middle of the crowd.  However, in one way she does get her wish.  The next song is "Bohemian Rhapsody" and even Sylvia is smiling.

Until the gunfire starts.  Wilf, Donna, and Zorba run out to find a soldier attempting to shoot an Atmos device to stop it from flooding its poison gas, but when he sees Donna he flips out, pointing his gun at her and demanding to see her back.  Despite Wilf's and Zorba's desperate attempts to protect her, he doesn't stand down until she puts her hands up and turns around.  The wild-eyed soldier incoherently apologizes and Wilf, former solider himself, starts verbally ripping strips off him.  

Donna just walks into the night.  "Hi," she says without surprise to Rose, who is just around the corner.

Rose delivers Atmos exposition until the sky burns above them.  Donna marvels, but Rose points out that this was the Torchwood swan song - Gwen and Ianto are now dead and Jack transported to the Sontaran homeworld.   "None of this was meant to happen," Rose tells Donna, dodging questions about herself and talking about the loss of the Doctor.  "Tall, thin man with great hair.  Some really great hair."  Rose tells Donna what the world was supposed to be, and how all the universes are in danger.  "It's coming, it's coming from across the universe and nothing can stop it."

Donna finally melts down.  "I'm nothing special!  I'm just a temp!  I'm not even that!  I'm nothing!"

"Donna Noble, you're the most important woman in the whole of creation."  

As a pickup line it has great promise, but Donna's not biting.  When Rose asks her to come with, the reply is "Blonde hair might work on the men, but you ain't shifting me."

Rose is impressed... but points out Donna will be coming with her in three week's time... but she also has to be certain, because if she goes, she's going to die.

Three weeks later, Zorba and his family are being packed into the back of a truck.  Zorba is characteristically trying to put a good face on it, giving huge hugs to everyone and telling Donna how much he'll miss her.  Donna, suffering from a sudden severe case of Situational Stupid, asks him where he's going and he replies that it's the new law - "England for the English and the oceans are still closed." He's being shipped off to a labor camp.

Strike Three for logic, which is now completely out of the game (and arguably out of the entire finale.)  How in heck do you close complete oceans? Nobody has said anything about a fuel crisis - there's probably a little more to go around with fewer people - so airplanes can still jump the Atlantic.  And looking at Europe, even if the south of England and parts of France are gone (Belgium is presumably wiped completely off the map) an easy hop by small plane or boat from northern England to Germany would lead to a clear land route back to Italy well out of the way of the presumed blast borders.  

Besides, if there's land and food enough to build and provision a concentration camp, there's land and food enough to build emergency housing.

With logic sitting out the rest of the episode, we go back to gut emotion. Wilf has plenty of horror ("That's what they called them the last time") and Zorba does a fantastic job of selling the fear underneath the forced humor but Donna still has Situational Stupid and doesn't even know what it means.  She's going to embarrassingly chase the truck down the road like a left-behind puppy wailing "Where are you going?" when even the youngest of viewers could tell her.

But Donna still hasn't quite given up.  Telling her unresponsive mother that she's been trying for jobs with the military, she tries to fish a compliment by saying "You were right.  I should have worked harder in school.  I suppose I've always been a disappointment."