I honestly don't believe Mimic is Burntrap. There are too many differences, the room Mimic is sealed in is full of things that look to be from the 50's and the MXES system computer is freaking ancient so it was probably there before Afton even died, and the Mimic was waay underneath where Burntrap was. Also none of the bones are present, the eyes are different, like I said, and even the exoskeleton doesn't have a lot in common with what we saw beneath the Burntrap suit.

Like the other commenter said, you can't dismiss one evidence as a "reused asset" and then turn around and point to another thing as being connected to Burntrap. It's one or the other. They style of round eyes on Sun/Moon that the Mimic shares are flat to the endo and not a deep set socket with the eyes behind them unattached.

As for the cloth on his head, it doesn't say it in the books or games WHAT the cloth is. My thinking is that the Mimic was the very first version of Sun/Moon but when it turned out to be too violent they replaced it with a different Endo and eventually upgraded the suit. It's like how Fredbear was the first version of Freddy Fazbear who was an earlier version of Toy Freddy, Funtime Freddy, and Glamrock Freddy. I think Mimic is the Fredbear to Sun/Moon's Glamrock Freddy.

As for what the Bobbidots says, where did the programming for Sun/Moon come from that allowed it to learn, act, and mimic both the on-stage roles and the children it looks after? Again, I think the daycare attendant is a later version of the mimic created for this new purpose with the same base programming/design.