This only happens on Cygnus characters, but yeah, that was a dumb move.
Can you enter the map where Shinsoo moves to after finishing the related quest?
If you mean the one in Leafre, I tried it and couldn't find it and I think it's a hidden street you can only access with the quest (from what I searched on the internet). Also, the photo location says "Shinsoo in Ereve", so doubt the camera would recognize it.
A small issue I see with this that then extra memory is being used up to keep track which char stored what. Either that or each (of the 46 possible) character would have their own storage (which if you try to make it fair, would be ~3 per the 46 char.)
[Apologies if I'm missing something completely about Reboot storage, never played Reboot.]