In the past, Zfetch has often given a single player some sort of 3P/anti TP role and have it relate to the poems or descriptions of his games. (Milk and his Mafioso judge role, Virt and Dreaming God come to mind). Not all games and descriptions are the same, but I speculate that the descriptions Zfetch give us could relate to a specific player already, not something that is going to happen in the future and hasn't already been determined.
You are right in your objective though. If I had to guess, the baseline setup we are looking at is a predominant vanilla town with maybe 1 or 2 special roles and some mafia goons. I would say there is at least a 50% chance of some 3P role or mechanic that acts separate from town or mafia action but that could be cleared up in further poems or actions.