Notice here the end game lobby shows two Mafioso's, instead of the original Forger role I think it was, though it doesn't matter specifically what Mafia role it is. Seems to be that whatever role you die as is what shows in the End Game Lobby.
A similar instance is that Vampires permanently change the role to Vampire, and they don't have the original role on the PC version, though I don't have images.
Here's the two Mafioso's: https://imgur.com/a/JyZBj7X