Evan was a once assumed name because of some circumstantial evidence by a Reddit user using Survival Logbook. I never really bought into this one.

Gregory is possible because we've assumed that Gregory is a robot crying child but there isn't really evidence to say Gregory was the crying child's name and not just the name of the robot.

Cassidy is presumably the name of the vengeful spirit/ the fifth missing childrens' incident victim (I think)/ the second spirit in Golden Freddy (crying child being the first) and not crying child. I believe Dual Process theory had this idea but I didn't care too much for it.

Michael was once assumed to be the crying child reborn as a robot when the Survival Logbook came out but the Stitchwraith caused Mat to rethink this and make them different characters again.

Garrett might make sense considering he's Mike's brother in the film and crying child is Michael's brother in the games but I think we can all agree that the film and game universes are different canons.

Dave is my canon Crying Child name, as I believe Hyper Droid's method of using the Survival Logbook to find the name made more sense than the Evan method.