Your fifth is ruled out by historical evidence. There survives nothing of any Christians who denied Jesus made the claims recorded in the Gospels. If they had existed, we'd have at least polemics against them (as we have polemics against Judaizers and Gnostics), if not their own works. Instead, nothing. If Paul of his followers had invented the claims, the anti-Paulicians would have said so. So would the Jewish authorities.
There are still three options.
Are you familiar with the Ebionites? The Pseudo-Clementine literature?
Over the centuries, the church became very efficient at stamping out "heretics" and destroying their literature. Most of what we know about early Christian "heresies" is from the work of writers who opposed them. The original, "heretical" works were destroyed. Those that survived, such as the Pseudo-Clementine corpus, did so by pure chance.