Vincent presumably "dies" on the night 5 phone call, in reality he faked his death and puts on the empty YellowBear suit that's stored in the parts and service room, the same suit he used to lure away and kill those children all those years ago.
On night 6 he starts becoming active, chasing down and attempts to kill Mike Schmidt but fails.

After this Vincent was never seen again. What happened to him or his whereabouts are now is unknown

Mike was shaken up, he never would've guessed someone was in this costume, let alone Vincent himself was the one in this costume and was trying to kill him.