Erm actually the mimic is burntrap, William is trapped in ucn. Aka his personal hell, you can’t exactly escape hell. Also if you look at the shape of the heads, the mimic and burntrap have very similar heads. Also scraptrap is missing an arm but when we see burntrap he has 2 arms. It’s possible that he was repaired but it would make more sense if the mimic was pretending to be burntrap. Also why would ffps and ucn exist if afton’s still out there, and why would they introduce the mimic in the first place if he’s not burntrap?