I know this is gonna get a lot of hate.  I would like to state, that I love Gundam, he's amazing, super great.  Easily in the top 5 of the DR2 cast.  That being said...

  
I don't think he's surviving for a few reasons.  I know he's really really well liked, but I'm talking from a narrative standpoint.  

  
Reason 1#  He essentially completed his arc in the original game, and on top of that made is very far, 4 trials in, in fact.  We learn that Gundam is a kind and honorable person even behind that mask.  He keeps it on so no one feels bad about voting him, and then sends his hamsters to Sonia.  It all felt complete.  It was like Sakura, yes he died but his arc essentially concluded with dignity and grace.  It wasn't unexplored like Imposter or Peko, or cut short like Hiyoko.  He was iconic from C1 to C4. 

Reason 2# What does he really have to do in this new scenario to warrant 10 full chapters across both timelines? I suppose they could come up with something fresh and new.  

Reason 3#  His va did say that they still didn't record any lines for him.  With the game coming out this year.  Having a survivor not have any lines recorded at that point is bizarre.

Reason 4# Other characters kinda...  Have arcs that weren't told or there's a whole other avenue to travel with them: Mahiru, Hiyoko, Peko, Mikan, Ibuki, Nekomaru, Imposter, Izuru (And yes even Teruteru), and you can throw in the other survivors (Minus Fuyuhiko who along with Chiaki are really the only ones I'd call fully resolved.)  I'm not sure, what else you'd really do with Gundam for 6 chapters besides having them just saying quips.  I suppose you could kill Sonia and Kazuichi off, but that kinda feels like what's gonna go down for Peko and it's a little redundant.

Reason 5# This is more of a meta reason but:  A very likeable character always dies C2 victim at least to me.  (And Gundam fits that bill.)  I don't know how or who'd do it, but I can see it happening Chapter 2 or 3.

  
Counter points:  1: He's really popular like I said.  2: they could explore his and Sonia's relationship more, having them bond over their shared interests, maybe she's a killer sparkling justice style and he has to deal with that fallout.

  
But yea...  I suppose I just see more potential in other characters.  And every tier list has the same 5 survivors usually: Hajime, Hiyoko, Peko, (Mikan/Ibuki), and Gundam.  It's just a bit expected.  Like we could get to see the imposter actually develop and fully realize as a person finding their identity, see Peko without her master and how she handles it, Teruteru's loneliness and him trying to actually make friends and not perv on everyone.  Mikan finding self-worth, Hiyoko learning to be independent, etc etc. 

  
(Anyway, those are my thoughts.  I just hope those who do survive get actual arcs and plot importance and aren't just shoved to the background of the game's Trio's show/spotlight like usual.)

Gundam in 2x2