That settles that then... There can exist multiple copies of the same role in the game.
I'm confused as to why this was in question, personally:
A SPECIAL NOTE: There are 10 secondary roles...all of the role names are completely different for each person, meaning that if there are two 'Doctors' in the game, they may instead be called 'Nurse', or it can be called 'Chef'...
There's 18 signups, 10 secondary roles, and no mention of vanilla players so secondary roles
have to overlap, as far as I can tell. It doesn't appear to be explicitly stated, though, so I guess I can see why it was being debated.