I thought he died then, but I could see a few hints during his execution, that he may have lived. The figure in the wheelchair looks so much like him, even if it was only his back.
After all, if he was just a daydream, why does he have to be in a wheelchair, specificially? Shouldn't he remain as he did in her memories? And if it was another person, why did he have to appear right after Charlotte's farewell?
So it's likely that he is alive, but will never meet Charlotte again... considering the nature of their parting, and how they're not meant to be together, plus how he's a terrible criminal designated to die, I don't think he's meant to ever show himself to the important characters anymore, because then they'll know he was spared. Perhaps Elle felt the need to spare him, thinking of Theo's words addressing why he became a monster. Theo could've been a monster, too, according to him. Maybe his supposed final words meant enough for him to be spared.
But I could be wrong. Still, I'm at least 80% convinced the guy in the wheelchair was him. It all seemed to line up.
Is Andre alive? Did elle let him live?