Maybe when Ella got that future-vision from Setrakus Ra in FoF and John got trapped in too, then everyone thought it affects Garde, but not humans, maybe it wasn't that. Maybe it was Ximic.
Think of it. Marina did touch Ella right before that, and nothing else changed before the others came in. When she touched John though, his Ximic probably came in and he copied her precognition or something. This happened before when he, Eight and Nine were having the same dream of Setrakus Ra. Maybe John doesn't have precognition like them, but he just copied it.
It also explains why he woke up during the attack but Ella didn't. Maybe it just stopped working. (Or just the scar, since Ella is not part of the charm).
John's whole Ximic situation is so funny, because in FoT, he was basically like: I have Ximic? No way. How come I never noticed before.
Also John:
*gets healing legacy right after meeting Marina*
*feels Six's invisibility on multiple occasions*
*joins Eight and Nine's precognition dream*
*joins Ella's futuristic vision*
*talks with Ella via telepathy alone on multiple occasions*
Yes, I wonder how he never noticed.











