guys idk if im right but im like prrrrrrrrretty sure marc's DID doesn't come from being an avatar .. if that were the case all avatars would develop DID and well,, clearly by the way they reacted ( EP 3 SPOILERS ) to arthur saying marc is unwell and crap they dont .. so like. making characters have DID just bcs they're avatars feels. kinda wrong.
then again im not 100% sure and i dont have DID myself so i cant rlly speak for the community