How is this possible?

In FuhNaff’s timeline video, he says that Afton dismantled the Classics to melt them into remnant, in order to inject them into the Funtimes.

If that is true, and the children’s souls are now within the Funtimes, how are they able to appear to Afton later to trap him in the Safe-Room for him to get springlocked?

I’m confused.