We're not saying anyone else came from heaven, we're saying the souls of the dead in Christ are in heaven now. Where else did John see the souls of the dead except in heaven?
Revelation 6:9 And when he had opened the fifth seal, I saw under the altar the souls of them that were slain for the word of God, and for the testimony which they held: 10 And they cried with a loud voice, saying, How long, O Lord, holy and true, dost thou not judge and avenge our blood on them that dwell on the earth?
Why can't you understand that what Jesus said in John 3:13 was as of the time He said that. It doesn't mean no one else went to heaven after that. Good grief. Soul sleep is a false doctrine. Period. It can't be defended with scripture.