Wouldn't the twin connection just make her evolve too she hasn't been dead for so long still I only see on evolution happening which makes the twins at level 2.
If Liz does 'evolve' its more likely that'd she would end up in a similar position to Oscar at that point (fucked up cause she evolved when she was dead, so monsterified).
He's the only other person I can recall ascending after he died but he was already infected by the monster blood mid fight (prior to his death) and didn't come back to life till a week later.
I just don't see Liz coming back from decapitation.
For all we know that damn dagger of Cole prevents such fuckery.
Its hard to know (or tell) too many unknown variables for now.
I mean fuck for all we know Cole could just fucking burn her head to nothingness the very next scene once the update drops.
No coming back from that now is there?