it makes perfect sense for a doll summoned into a dreamer’s dream room to represent a part of that person’s Platonic makeup - a puppet in the subconsciousness of every troll representing a fear of Lord English, but also the fact that every troll has a bit of Lord English in them, for example - because that’s what the dreamself (and by extension the dream room) is; someone’s very Platonic essence.
what’s troubling about this idea is that it could be taken as meaning that a subjugglator having the power to mess with people’s dreams also means that a subjugglator has the power to change someone’s very essence… but of course, the chucklevoodoos don’t just “create” puppets ex nihilo: they “psychically amplify fears through dreams”! the chucklevoodoos are in fact the psychic ability to perform persona alchemy, externalising the most internal aspects of a person!
Gamzee didn’t “make” John afraid of clowns; rather he just emphasised what was “always there” in John’s innermost mind. Dream rooms work like this all the time; the MEOW code that Jaspers supposedly whispered to Rose merely unlocked what she had already scribbled all over her dream walls, and the Sweet Bro and Hella Jeff scrawlings in Dave’s sanctum explain how Dave came to think of the same idea in two completely different lifetimes, even though his apparent inspiration only happened in one of them. There is essentially nothing new in paradox space; all ideas come from somewhere, either locked away in someone’s genetic memory or floating around in the void. And Gamzee’s summoning of Lil Cal into Dave’s subconscious is only a very literal example of this; though we may at first be led to believe that this is the “starting point” in Cal’s timeline, we later find out that he was only reconstituting something that had been banished to the void by someone else’s hand!